Joe Friel's Blog, page 8

Aging: Customizing the Build Period

In my last three posts (here,  here, and here) I offered suggestions for how a senior
athlete may customize the training routine in the Prep and Base periods to
allow for more frequent and deeper recovery to improve the quality of training
while reducing the risk of injury. Recovery is likely the secret for the older
athlete wanting to preserve or even improve performance. I tried to show how
using either 7- or 9-day microcycles plus a regular R&R break could foster
better recovery. I’d highly recommend the 9-day if you can shoehorn it into your
lifestyle. In this post I will offer similar suggestions for periodizing the
Build period.

Starting about 12 weeks before your first A-priority race and lasting
9 to 10 weeks, this mesocycle ultimately determines how well you perform on
race day (Morton). Get it right and you can feel confident going to the start
line. Mess it up, mostly through inconsistent training (which I’ll discuss in a
subsequent post relative to senior athletes), and you’ll be extra nervous and
filled with self-doubt on race day. If ever there is a time to be completely
devoted to your training, this is it.

One of the reasons for this importance is that the workouts are
becoming increasingly race-like. For the first time in the season you’re
actually training to race. Leading up to the Build period you were training to
train. The purpose of Prep was to gradually return to structured training. The
Base period was for developing general physical fitness thus increasing your
capacity for handling high-stress training in the Build period.

So far you have done quite a bit of strength training. By the Base 3a
and 3b periods this is taking a backseat to your sport-specific fitness
program. Strength Maintenance (SM) is now the phase you’re following. (Again,
see my Training Bible book
for the details of strength periodization or
go here for triathlon
or here for cycling for details. Scroll to the bottom of the page
for these latter two.) SM continues into the Build period. It should now be
rather low-key and never leave you so wasted as to negatively impact your
sport-specific training. In other words, strength training is of secondary
importance now. The primary focus is on race-like training and continuing to
develop aerobic capacity.

You’ve also done a bit of high-intensity, aerobic capacity training
every microcycle of the Prep and Base periods in the form of fartlek workouts. Their
purpose, you’ll recall, is to slow the decline in your VO2max which has been
shown repeatedly in the research to be one of the most common causes of
performance decline with aging. You’ve done one such short workout every 7 to 9
days to gently allow your body to gradually adapt. By now with 12 or more of
these sessions behind you, your body should feel adjusted to small amounts of
such stress allowing you to step it up a bit in the Build period. So let’s take
a look at how to do that.

For A-priority events of less than about 4 hours, I suggest you
continue doing a high-intensity session once per microcycle in the Build period.
You should be able to step it up from fartlek to intervals with each rep approaching
your aerobic capacity (as described here).

For long events (greater than about 4 hours), high-intensity training
in Build is much like it was in late Base for the short-event athletes with an
emphasis on intensity somewhat below lactate threshold. For the long-course
athlete, aerobic capacity sessions may still be done once per microcycle but in
the Build period it is only for maintenance. Since the long-course athlete did more extensive aerobic
capacity training in Base 3a and 3b, somewhat lower-key, unstructured fartlek
sessions now become the preferred workout type for VO2max maintenance. A few
minutes of such high intensity done occasionally now will maintain the gains
made in Base. The exception is road cyclists. Since the outcomes of these races
are often determined by episodes of very high intensity lasting about 5 minutes or
less, at or even exceeding VO2max, it’s imperative that the serious road racer
do similar intervals in the Build period even when the race is longer than 4
hours.

Below are examples for this period using both 9- and 7-day
microcycles with each starting on the day after Base 3b finished (note that Build 2 is repeated in both
examples). The red highlighted days are when you should do either an aerobic
capacity workout or one that mimics what is expected on race day. This is most
certainly race-like intensity, but could also include race-like duration or a sizeable
portion thereof. Some race durations are simply too great to be done
repeatedly, such as for an Ironman triathlon. Whereas others, for example a 5km
running race, are easily repeatable durations in a workout. Besides intensity
and duration, the red-highlighted days should also mimic as closely as possible
other expected conditions of the race such as terrain, weather, time of day,
equipment and nutrition.

In the following 9-day microcycle example, the black days in Microcycles 1 and 2 are
for short-term recovery. The first of these two days could be a day off or
low-intensity and short-duration workout. What you do with the second day of
the pair depends on how quickly you recover. Those who bounce back relatively
quickly should be able to do a moderate to long-distance aerobic threshold
(zone 2) session. Others who still are carrying a significant amount of fatigue
by the second day should simply repeat the previous day – a day off or low
intensity and short duration. The 5-days of R&R in Microcycle 3 are only
for rest and recovery. That means low intensity and short duration.

9-day microcyles (69 days total)

Build 1 – 23 days

         Microcycle 1 – 9 days
(S,
M, T, W,
T, F, S,
S, M)

         Microcycle 2 – 9 days
(T,
W, T, F,
S, S, M,
T, W)

         Microcycle 3
(recovery) – 5 days (T, F, S, S, M)

Build 2a – 23 days

         Microcycle 1 – 9 days
(T,
W, T, F,
S, S, M,
T, W)

         Microcycle 2 – 9 days
(T,
F, S, S,
M, T, W,
T, F)

         Microcycle 3
(recovery) – 5 days (S, S, M, T, W)

Build 2b – 23 days

         Microcycle 1 – 9 days
(T,
F, S, S,
M, T, W,
T, F)

         Microcycle 2 – 9 days
(S,
S, M, T,
W, T, F,
S, S)

         Microcycle 3 (recovery)
– 5 days (M, T, W, T, F)

7-day microcyles (63 days total)

Build 1 – 21 days

         Microcycle 1 – 9 days
(S,
S, M, T,
W, T, F,
S, S)

         Microcycle 2 – 7 days
(M, T,
W, T,
F, S,
S)

         Microcycle 3
(recovery) – 5 days (M, T, W, T, F)

Build 2a – 21 days

         Microcycle 1 – 9 days
(S,
S, M, T,
W, T,
F, S,
S)

         Microcycle 2 – 7 days
(M, T,
W, T,
F, S,
S)

         Microcycle 3
(recovery) – 5 days (M, T, W, T, F)

Build 2b – 21 days

         Microcycle 1 – 9 days
(S,
S, M, T,
W, T,
F, S,
S)

         Microcycle 2 – 7 days
(M, T,
W, T,
F, S,
S)

         Microcycle 3
(recovery) – 5 days (M, T, W, T, F)

As with the Base period, these mesocycles could be modified in many
ways to better match your situation. Don’t be afraid to experiment.

In the next installment I’ll walk you through how to customize your
Peak and Race periods to match your needs as a senior athlete.

References

Morton RH. 1997. Modeling training
and overtraining. J Sports Sci 15(3):335-40.

Aging: Other Base Period Training and Microcycles

I’m back home after a two-month stay in beautiful Tuscany. As much
as I enjoyed the riding there, it’s a great relief to back where the two-way
roads are wider than one car. Taking the many blind corners on narrow mountain
roads at high speed often got my heart rate higher than the workout effort
would suggest. It will also take awhile to adjust to being back where drivers are
often angry with anyone on a bike. I’m not sure which is worse.

Now back to the topic at hand – aging and performance…

So far I’ve been trying to summarize what the research suggests are
the primary reasons endurance performance declines with age. As a quick review, here
are what appear to be the culprits:

Aerobic capacity (VO2max) declining at the rate of 10% or more
per decade
Muscle mass losses of greater 10% per decade

It appears there are several reasons for these huge changes, not
the least of which are weight
gain (more body fat) and the reduced production of anabolic
(tissue-building) hormones. 

These changes would seem inevitable. In fact, Carl Foster and his
associates at the University of Wisconsin in La Crosse reviewed the aging
literature and reported that “there appears to be a loss in functional capacity that cannot be
overcome by training.” They continue, “older athletes may be limited primarily
by the inability to maintain the same volume and intensity of training. Also,
older athletes appear to respond more slowly to the same training load than do
younger athletes.”

While this may sound unavoidable and even depressing, bear in mind
that most of what we know about the aging process is based on studies of “normal”
subjects – meaning sedentary old people. As the Boomers have reached their 50s
and 60s in the last few years the research has become somewhat more positive. We’re
learning more about what is possible by studying those who have pushed their
physical and mental limits. As a result, it appears that about half of the loss,
or perhaps even a greater portion, is due to disuse, not aging per se. For
example, a review of the research by Lewis Maharam and associates points out that most of the changes that come with
aging “have been found to be actually the result of a long-standing sedentary
lifestyle.” So we can probably dismiss the results of much of the aging
literature until recently.

That’s been my take-home message in the preceding posts. We shouldn’t
accept the high rates of loss as being inevitable. We have some control over
these losses and how rapidly they occur by employing measured doses of high-intensity
training. Continuing to do only long,
slow distance (LSD) workouts, as many of us do as we age up, has a quite
limited effect on preventing a rapid loss of performance. It’s just a higher
level of disuse than that of the sedentary senior citizen. The body only
responds by growing stronger and fitter if it is challenged. A steady diet of
LSD, while it is quite effective for the aging novice athlete, does little for the highly experienced senior
athlete who has been training with LSD year after year. That’s no longer a
challenge for the aging body.

That’s how I started down this path of training with more intensity
in order to maintain or even improve performance. It doesn’t mean, however,
that high-intensity training should be your only training mode. As with almost
everything in life, it isn’t an either-or solution. It’s a mix of high-,
moderate- and low-intensity that is most likely to boost your physical
performance. Most senior athletes have the moderate and low parts down pat. We
just need to add some higher intensity training which has been shown to boost
aerobic capacity and strength while stimulating hormone production.

In the previous
post I discussed how to incorporate aerobic capacity and strength training into the
Base period. But as I explained, there’s more to it than just high intensity and
weights. You should not neglect the other training abilities I describe in my Training Bible books. In the Base period you still need to include aerobic endurance, muscular force (sport-specific) and speed skills training as
described here. By Base 3a and 3b you should also include the
starting levels of muscular endurance workouts, initially in zone 3 (power,
pace or heart rate). See my Training
Bibles for the details of how to do each of these.

In Base 2, 3a and 3b, when training for events lasting roughly 4
hours or less, muscular endurance workouts are done with increasing frequency
and for longer durations as strength training, which reached a peak by Base 2,
decreases both in terms of workout time and total workload. By late Base 2 and
continuing throughout the remainder of the Base, Build and Peak periods,
strength training moves into a maintenance mode. Aerobic capacity workouts at this
time, while slightly increasing in volume, remain rather brief. Muscular
endurance gradually becomes the primary focus.

For events longer than
about 4 hours, sport-specific training may become somewhat more intense in the
late Base periods with an emphasis on workouts exceeding the lactate threshold.
This is in keeping with the concept that Base training is “unlike” the race. So
when training for an event longer than about four hours, now is the time to
emphasize high-intensity, aerobic capacity training (my pace and heart rate zone 5b or Coggan’s power
zone 5). Events longer than 4 hours seldom are dependent on aerobic capacity efforts
(with the possible exception of bicycle road racing) so it’s best to do such training
early in the season - late Base - and then in the Build period shift the focus to
event-specific intensity.

For the senior athlete the Base mesocycles may look something like
the following. The daily workout routine for the nine- and seven-day
microcycles is more completely described in my previous post. Note that for the senior athlete Base 3 is
repeated.

Base Period 9-Day Microcycle

Day 1         High dose (aerobic
capacity)

Day 2         Recovery day
(off, active recovery, or cross train)

Day 3         Recovery day (active
recovery or aerobic endurance)

Day 4         High dose (strength
and aerobic or muscular endurance)

Day 5         Recovery day
(off, active recovery, or cross train)

Day 6         Recovery day (active
recovery or aerobic endurance)

Day 7         High dose (strength
and aerobic or muscular endurance)

Day 8         Recovery day
(off, active recovery, or cross train)

Day 9         Recovery day
(active recovery or aerobic endurance)

Base Period 7-Day Microcycle

Day 1         High dose (aerobic
capacity)

Day 2         Recovery day (strength
and off or active recovery or cross train)

Day 3         Recovery day
(active recovery)

Day 4         Moderate dose (aerobic
or muscular endurance)

Day 5         Recovery day
(off, active recovery, or cross train)

Day 6         Moderate dose (strength
and aerobic or muscular endurance)

Day 7         Recovery day (off,
active recovery, or cross train)

Note: I’ve found that strength training is best done either after
the sport-specific workout or several hours before to allow for muscular recovery
to reduce the likelihood of injury. This is especially a concern for running.

Again, the above and what I’ve described in previous posts on
periodization are only suggested Base period routines. Yours could be designed
in any number of different ways, such as longer or shorter microcycles, more or
fewer mesocycles, longer or shorter recovery microcycles and how the daily
workouts are arranged. The total workload of the sport-specific workouts
(“aerobic or muscular endurance”) can also be adjusted to match what you are
capable of physically managing relative to recovery while keeping a low risk for
injury and overtraining. In other words, adjust the above suggestions to better
fit your unique needs.

In the next aging posts I’ll provide a similar breakdown for the
Build, Peak, Race and Transition mesocycle periods.

References

Foster C, Wright G, Battista RA, Porcari
JP. 2007. Training in the aging
athlete. Curr
Sports Med Rep 6(3):200-6.

Maharam LG, Bauman
PA, Kalman D, et al. 1999. Masters athletes: factors affecting performance.
Sports
Med 28(4):273-85.

Aging: Customizing the Base Period

I’ve been writing about aging here since June. This rather long series started
when I realized this past spring that in December I’d age up to 70.
There’s an old saying that it takes 10 years to get used to how old you are.
That certainly is the case with me. I never imagined I’d one day be such an old
geezer. I've only recently gotten use to saying that I'm in my 60s. But now that I’m almost 70 I’ve come to realize that it really isn’t all that
bad.

I’ve been a serious athlete all my life and I think that has helped
to soften the blow. It’s mostly a mental challenge. This summer, however, I saw a drop in
performance. It wasn’t huge, but it was the first I’d seen in a couple of
decades. Why did it happen? I didn’t know. So I decided to go back and read the
research to see what is being discovered about the aging process, especially as
it relates to athletes, and how I might possibly slow or even reverse it. Perhaps I could find a solution. The last time I did
this I was then in my early 50s and experienced the same slight downtick in
performance. That was in the mid-1990s when I wrote a book called Cycling Past 50. (That's me on the cover.) There weren’t many studies available on the
topic then.

What I’ve discovered this time around is that there has ben a
tremendous swell of research on aging in the last 15 years. That’s what I have
been describing in these blog posts until about two weeks ago. Then the topic
shifted slightly, but to a related topic – how to manipulate the time we
dedicate to training. That’s called “periodization.”

Due to coaching older athletes and myself, in the last two decades
I had come up with ways to modify periodization to better serve the aging
athlete’s recovery and injury-avoidance needs. So that’s what I’ve been trying
to describe for you recently. I’m afraid it’s become somewhat textbookish, and
I apologize for that, but I’m afraid this topic doesn’t lend itself to exciting
prose.

What I’m doing now is taking you through these periodization and
aging discoveries I made years ago. I hope you’ve been able to hang in there
with me throughout this sport-sciencey discussion. As a serious senior athlete
or a coach who trains such athletes, I know this has the potential to improve
performance by slowing the aging process, reducing the risk of injury and
boosting those aspects of fitness that are most likely to produce results. I’ve
seen it happen many times.

So with all of that in mind, let’s return to periodization for the
senior athlete, starting with the Base period.

The Base period follows Prep. Base is described in my books as being three sub-periods, each four weeks long.
For the senior athlete, however, I divide it into four sub-periods: Base 1,
Base 2, Base 3a and Base 3b. The reason for the added fourth cycle is that I
shorten each of them to provide more frequent R&R as explained here. Using this four sub-period model and either nine- or seven-day microcycles, your Base mesocycle would look something like this:

Base with 9-day microcyles (92 days total)

Base 1 – 23 days

         Microcycle 1 – 9 days
(M, T, W, T, F, S, S, M, T)

         Microcycle 2 – 9 days
(W, T, F, S, S, M, T, W, T)

         Microcycle 3
(recovery) – 5 days (F, S, S, M, T)

Base 2 – 23 days

         Microcycle 1 – 9 days
(W, T, F, S, S, M, T, W, T)

         Microcycle 2 – 9 days
(F, S, S, M, T, W, T, F, S)

         Microcycle 3
(recovery) – 5 days (S, M, T, W, T)

Base 3a – 23 days

         Microcycle 1 – 9 days
(F, S, S, M, T, W, T, F, S)

         Microcycle 2 – 9 days
(S, M, T, W, T, F, S, S, M)

         Microcycle 3
(recovery) – 5 days (T, W, T, F, S)

Base 3b – 23 days

         Microcycle 1 – 9 days
(S, M, T, W, T, F, S, S, M)

         Microcycle 2 – 9 days
(T, W, T, F, S, S, M, T, W)

         Microcycle 3
(recovery) – 5 days (T, F, S, S, M)

Base with 7-day microcyles (82 days total)

Base 1 – 19 days

         Microcycle 1 – 7 days
(M, T, W, T, F, S, S)

         Microcycle 2 – 7 days
(M, T, W, T, F, S, S)

         Microcycle 3
(recovery) – 5 days (M, T, W, T, F)

Base 2 – 21 days

         Microcycle 1 – 9 days
(S, S, M, T, W, T, F, S, S)

         Microcycle 2 – 7 days
(M, T, W, T, F, S, S)

         Microcycle 3
(recovery) – 5 days (M, T, W, T, F)

Base 3a – 21 days

         Microcycle 1 – 9 days
(S, S, M, T, W, T, F, S, S)

         Microcycle 2 – 7 days
(M, T, W, T, F, S, S)

         Microcycle 3
(recovery) – 5 days (M, T, W, T, F)

Base 3b – 21 days

         Microcycle 1 – 9 days
(S, S, M, T, W, T, F, S, S)

         Microcycle 2 – 7 days
(M, T, W, T, F, S, S)

         Microcycle 3
(recovery) – 5 days (M, T, W, T, F)

The Base period is considered by many coaches as the most important
time of the year since the athlete’s general fitness when it’s all over determines
how much training stress is manageable in the following Build period. If Base
period training is compromised for whatever reason, then the likelihood of
having a high peak of fitness for the race is reduced.

To accomplish this high level of general fitness, coaches and
athletes typically believe that in the Base period training volume (hours,
miles, kilometers, meters, TSS, etc) should be high and intensity relatively
low. The serious senior athlete who has been in his or her sport for a decade
or more will see little in the way of gains, either in terms of seasonal
performance, or the long-term slowing or reversal of the aging process
(declining aerobic capacity and muscle mass) by focusing training only on
volume. The key to these goals is measured doses of high-intensity training
mixed in with the more Base-traditional moderate and low-intensity training.
Bear in mind that the volume of training must be reduced if the intensity is to
be raised, even if by what seems a small amount as was done in the Prep period. 

To improve seasonal aerobic capacity and to maintain or build
muscle mass, the type of training program that was started in the Prep period
must be continued and enhanced in Base. This involves interval-type training
and resistance exercise. Let’s look briefly at how each of these changes from
Prep to Base.

Aerobic Capacity

In the Prep period aerobic capacity (VO2max) was targeted by
including a once-per-microcycle fartlek session with a combined total of 3 to 5
minutes of high-intensity power (Coggan’s zone 5) or pace (my zone 5b). If you
are a triathlete, that does not mean one per sport, but rather only one such
workout in a microcycle. In other words, once every seven to nine days. This is
best focused on your weakest sport. If in doubt, do this workout on the bike.

Now as you move into the Base period you should boost the high
intensity workload slightly by increasing the amount of time in zones 5/5b. Start
at about 5 minutes per microcycle and over the course of a few microcycles
gradually double it. At this point the triathlete may divide the total zone
5/5b total time between two or even three sports. By the end of the Base period
you should be achieving about 15 minutes of total aerobic capacity –fartlek or
intervals – in a microcycle. As always, the devil is in the details. Some
athletes will be able to progress at a much faster rate than others. The key
here is to increase the workload cautiously and conservatively. I can’t put
enough emphasis on this. The worst thing that could happen is an injury related
to pushing too hard. Be patient.

Strength Training

In the Prep period you should have started weight training following
the guidelines for the Anatomical Adaptation (AA) phase in my Training Bible or as described here (scroll to bottom of page). By the end of Prep
you should have mastered the skills involved in each exercise and be ready to
increase the loads while reducing the reps. Follow the suggested details and
progress to the Max Transition (MT) then to the Max Strength (MS) phases in
Base 1 and 2. Do not attempt heavy load training until each individual exercise
skill is mastered with light loads. Doing so could result in an injury-related
setback in training or even permanent damage. If unsure how to do the exercises,
seek help from a personal trainer where you workout. (By the way, I am often
asked if strength training hours “count” as part of the accumulated time of
this period. They do indeed.)

That’s plenty for today. In the next aging-series post I’ll cover
Base period training for workout types other than aerobic capacity and
strength, and provide suggested for microcycle workout routines.

The next post may be delayed a few days as I’ll be traveling back
to Arizona from Tuscany where I’ve been training for the last two months. It’s
been great fun. Now back to reality.

Aging: Customizing the Prep Period

In recent posts I’ve been describing how you can alter
periodization to allow for better recovery and higher quality training at the
same time by altering the length and design of your microcycles and mesocycles. 

If you’ve read my Training Bible you may recall that there are six
mesocycles in a season. It starts with the Prep period and progresses through
Base, Build, Peak, Race and culminates with the Transition period at the end of
the season. In the following posts I’m going to specifically show you how to slow
or even reverse the aging process by doing workouts for aerobic capacity and
strength training in each of these periods. This calls for high-intensity
training which increases your risk of injury (as I’ve said soooo many times
here). How you can reduce that risk and still improve race performance is our
focus today. In this post we’ll examine the Prep period. Since it’s fall in the
northern hemisphere you may well be in that period right now or about to start
it. In the southern hemisphere it’s spring so your current period is likely
late Base or early Build. The remaining five periods will be covered in the
next several posts.

The Prep period is the start of the new season when you return to
training after a well-deserved break from structured workouts (the Transition
period, which was the culmination of the previous season). Prep starts very
roughly 6 to 7 months before your first A-priority race of the next race
season. The Prep period’s characteristics are minimal structure, mostly low
intensity and cross-training along with the early stages of gym-based strength
work. After about one to six weeks of Prep you are ready to enter the Base
period. How long it is depends, in part, on what you’ve been doing in the
previous weeks. Of all the periods, Prep has the least-defined duration. For
example, athletes who took a long Transition period may have morphed it into a
Prep period and so don’t need a lengthy Prep, or they are ready to immediately start
the Base period.

The serious senior athlete should consider doing one aerobic
capacity and one or two strength sessions (the Anatomical Adaptation phase –
see my Training Bible books or go here and scroll down to “Training Workout”) in a microcycle, such as a week or nine
days as I explained in a previous
post. 

As I have suggested before, as a senior athlete who is new to
high-intensity workouts such as intervals or fartlek, especially if your family
has a history of heart disease or you are taking any medications, it’s a good
idea to consult with your doctor before beginning such training.

Also consider that if new to high intensity training and have a
history of injuries related to exercise then you need to consider how to reduce
your risk before starting to do such workouts. I’ve always had athletes I’ve
coached see a physical therapist who is experienced working with athletes before
starting the Prep period. The visit is to get a head-to-toe examination to find
what the causes of such injuries may be and how to prevent them in the future.
This may involve certain strength or flexibility exercises, a bike fit, shoe
selection, orthotics or other modes of correction.

Once you have a clear bill of health, in order to start building
your aerobic capacity, unstructured fartlek workouts are preferable now as
explained here. These don’t have to be in your primary sport in
the Prep period. Since these workouts now have a central rather than peripheral
focus, maintaining the heart’s stroke volume (blood pumped per beat) is the
purpose of such training. Your heart doesn’t know if you are running, cycling
or climbing stairs, so cross training is now an option for aerobic capacity
training. Later in the season the aerobic capacity training focus shifts to the
peripheral muscles of the arms or legs, depending on your sport. Sport-specific
workouts are necessary then. Cross training will no longer be advantageous.

In the Prep period keep the aerobic capacity work intervals very short,
less than a minute, and the recovery intervals long, at least as long as the
preceding work interval. How long they both are depends on how you feel at the
time. Always stop such workouts well short of failure. Don’t try to find your
limits. Be patient. Do only a small amount of total high-intensity time,
perhaps 3 to 5 minutes in a workout, once in a microcycle.

With aerobic capacity and strength training don’t try to test your
limits in the Prep period; don’t even come close. Train very conservatively. In
fact, think of it as “exercise” or even “play” instead of “training.” That’s
why an unstructured fartlek workout is so good now. “Fartlek” is a Swedish word
for “speed play.” That’s exactly what you’re doing. The only aspect of your routine
now that should resemble training is strength development. But, of course, this
is also cross training.

Avoid accumulating fatigue over several days during this period. You
should feel quite fresh and rested every
day. One of the low-key, aerobic capacity sessions described above and two "AA" strength workouts (see my Training
Bible) in a microcycle are the only times in this period when you do what could be
called “hard” efforts, and they are quite limited to prevent injury and weariness.

A five-day R&R break isn’t necessary at the end of Prep as it
is in the Base and Build periods as the training is not very challenging. Once
you feel you are physically and emotionally ready to start structured training
go immediately into the Base period. I’ll discuss how seniors may consider
training for that in the next post.

Aging: Flexible Periodization

In the last few aging posts I’ve been walking you through how you
can customize your periodization to more closely match your age by focusing on
the recovery side of the training equation. I hope you are giving some thought
to how you can adjust your microcycles
and mesocycles to ensure that you come into the key workouts with adequate recovery. That will
boost your fitness while helping you to slow, or even reverse, the decline in
performance typically seen with aging. And planning based on getting adequate
recovery after hard days will help you avoid injury.

After you come up with a plan it’s critical that you are flexible in
applying it. So what does flexible
mean? It means paying close attention to how you feel. If you are not feeling
rested enough to do a high-dose workout, even though one may be planned for
that day, reduce its difficulty — intensity, duration or
both. Or even consider taking the day off if your fatigue is great enough. Training
through deep fatigue will only result in a poor quality session and more
fatigue – not better fitness.

Periodization is only a tool to help you train more effectively. Too
many seem to see it as a rigid dictum requiring you to do every workout as
scheduled regardless of how you feel at the time. Considering it as such is a
sure way to end up injured or overtrained.

There are a few athletes – and I do mean “few” – who are so in-tune
with their bodies and have such a depth of experience with training that they
don’t need detailed training plans. You may know of a good athlete like this
who expresses disdain at periodization and planning. Yet they do good workouts,
recover well and have great races. Regardless of what they may say, however, they
do have a plan. And they are periodizing. It just isn’t written
down and worked out in detail on a daily and weekly basis as I’ve been
suggesting. It’s in their heads. They know what needs to be done and when. Dose
and density are always on their minds even if they don’t know what the terms
mean. What they’re doing is called “periodization on demand” and “recovery on demand” (here and here) which work well for a few athletes. Most are
incapable of training this way because they give only lip service to “listening
to their bodies.” In reality most follow the philosophy of “never enough.” That
almost always results in breakdowns such as an injury or overtraining when not
following a well-designed plan.

In the next post in this series I’ll suggest an overview to periodization
at the macrocycle (seasonal) level with adjustments made for senior athletes.
By the time we’re done with this planning stuff you’ll be able to train more
effectively and race faster. Hang in there with me. We’re almost done. Only a
couple more periodization posts. I know this probably seems a lot more
complicated than what you expected. But the payoff next season and for years to
come is significant. 

Aging: Matching the Mesocycle to Your Recovery

A reader asked me a few days ago if aerobic capacity training,
which is what I suggest you probably need a bit more of in your training if
you’re a typical senior athlete, means you should aim to reach your VO2max
heart rate – which is near maximal heart rate – every time you do such a
workout. In short, the answer is “no.” Here’s the details.

If you’re training with a heart rate monitor (which is the least
effective way to do intervals due to heart rate lagging effort early in the
session and within each rep) you should aim for heart rate zone 5b with each
interval. You may not be able to achieve that on the first two or three
interval reps due to HR lag. The 5b zone starts 3 beats per minute above your
lactate threshold heart rate (which is the intensity at which you begin to
“redline”) and tops out short of your max HR (see my Training Bible or Total Heart Rate Training books for zone details by sport). For the first few intervals when using a HR monitor,
base your effort on perceived exertion – above your perceived redline.

If you’re a cyclist or triathlete using a power meter, use Coggan’s zone 5 which also starts just above FTP (similar to LTHR – when you begin to redline)
and rises to about VO2max power. As a runner or swimmer doing intervals based
on pace, use my pace zones
5b. These zones do not require that you
achieve your max HR or even max effort with every interval (also recall that I suggested this could be
fartlek or hill work, or even a fast group workout). Your effort should exceed your redline to be affective in achieving the goal we
are seeking here – to boost your aerobic capacity.

Power and pace are by far the most effective ways to do intervals.

As a quick review, the intervals I’m suggesting here are 30 seconds
to 5 minutes long with equal recovery durations after each. Do a total of 5 to
15 minutes of combined interval time within a session. Start with the low ends
of both – 30 seconds and 5 minutes. As the season progresses you should be able
to do longer intervals with more total interval time. Again, these can be done
as fartlek (meaning unstructured and based entirely on “feel” for durations and
intensity), as hill repeats or even as a group workout that includes several
fast portions.

As I’ve mentioned before, intervals increase your risk of breakdown.
The most common is injury. But one of those risks may be related to heart
disease. If you have reason to believe there is something cardiovascularly
risky for you in doing high-intensity intervals (for example, a history of
heart disease in your family), see your doctor before starting such a program.
In fact, as a senior athlete, it’s probably a good idea to get a check up
regularly regardless.

Now back to periodization for the senior athlete.

In the last aging
post I discussed how to customize a short period of your training, such as a week or
a few days – a “microcycle” in periodization-speak – to match your personal rate
of recovery. You may recall that I suggested training in nine-day cycles if you
can fit it into your lifestyle. That’s not possible for many so I also offered
suggestions on how to use a more common seven-day cycle in such a way as to
reduce your risk of breaking down.

Let’s do something along the same line for the next longer period
of time in your training plan – the “mesocycle.” This is typically a grouping
of two or more microcycles. For example, the Base and Build periods are
mesocycles.

In traditional periodization, Base and Build are generally four
weeks long – 28 days – with the last few days intended for rest and recovery
before starting the next mesocycle. But as a senior athlete I’d suggest making
these shorter – about 19 to 23 days. This allows for more frequent rest and
recovery, which is what you do in the last few days of a mesocycle.

Nineteen to twenty-three days would be the combination of two
microcycles of either 14 days (2 x 7-day microcycles) or 18 days (2 x 9-day
microcycles). Then add five days for R&R on to the ends of both of these. That
makes for 19 (14 + 5) or 23 (18 + 5) total days in the senior athlete’s
mesocycle. So now your R&R will occur more frequently than if you were
doing a 28-day mesocycle. And since recovery is one of the major obstacles to
senior performance, this has the potential to boost your training quality and
therefore your race performace.

Five days of rest and recovery are usually adequate to shed the
built-up fatigue of the last mesocycle before starting the next. But it could
be that you need more or less time at the end of a mesocycle to recover. In
that case adjust the total number of mesocycle days to match your needs. This
can be done “on the fly,” depending on how you feel at the time. Still a bit
tired after 5 days of R&R? Take another day to rest up. Feeling great after
3 days? Start the next mesocycle with a longer-than-usual microcycle.

How long you take to recover mostly depends on how challenging the
preceding microcycles were. The senior athlete usually knows that the more
high-intensity training that was done, the more R&R that is needed. For
example, you may find that R&R after a Base mesocycle requires less time
than after a Build mesocycle. Adjust the number of R&R days accordingly. If
unsure, allow for more to get rested up. One of the biggest mistakes you can
make in training is to start the next mesocycle slightly tired. It just
snowballs from then on.

If you’re doing seven-day microcycles in a 21-day mesocycle and
need only five days of recovery at the end (few athletes, even seniors, need
seven days for R&R), that leaves you with two “extra” days (7 + 7 + 5 = 19,
21 – 19 = 2). This means that the first microcycle of the next mesocycle would
be nine days instead of seven. So you could, essentially, increase the density
of your training by adding one more high- or medium-dose workout at the start
of the next period. Another option is to use one of those days to measure your
progress with a field or lab test (these are described in my Training Bibles). Then, after a day of rest, return to your
normal, seven-day training microcycle.

I hope that this and the previous post on microcycle design are helping you plan your training to better match your individual dose and
density needs. I know all of this periodization stuff is a bit tedious, but
time devoted to such planning now will pay off with better training later on because
you will work on what’s important while getting adequate recovery. Quality
training and recovery are the two keys to effective training. And recovery
seems to be the greatest challenge we have as senior athletes.

In the next aging post I'll touch briefly on flexible periodization.

Reverse Periodization

Yesterday
on a recovery ride around Tuscany with Jesper Olesen, a Dane I met in Lucca
where I’ve been training for the last several weeks, he asked me about
something that always gets me going – “reverse periodization.” Would it be wise
for him to train that way since getting in high volume is difficult in the
winter?

Before
getting into my answer, how about if I first explain what reverse periodization
means.

The typical
explanation is that it’s a way of organizing training so that in the Base
period the athlete does short duration and low volume, but high intensity –
especially above the lactate threshold. Then in the Build period the intensity
is reduced to below the lactate threshold and workout duration is increased
resulting in higher volume. I know that sounds very inviting to many athletes,
but there’s a basic flaw in the thinking, which doesn’t necessarily make
training in this way wrong. It just makes the concept wrong-headed. I’ll
explain that.

The concept
of reverse periodization makes a basic, flawed assumption: all athletes,
regardless of the event they are training for, when using “standard” periodization
should do high duration/volume in Base and high intensity in Build. That’s why
its proponents call their concept “reverse” periodization. But that’s not
exactly the way periodization is meant to work. It’s not always high
duration/volume before high intensity and then the race.

The basic
premise of periodization is this: The
closer in time you get to the A-priority race you’re training for, the more
like the race your training should become. Doing just the opposite – making
your workouts more unlike the race as
you approach it – would be counterproductive. You’d go to the start line having
done few workouts like the race.

For many
events and athletes, intensity is the key to performance. Using reverse periodization, when an athlete goes to the start line it may have been
several weeks since any race-like intensity was done. He or she has been focused on duration and volume instead. Or at best, only a small amount of race-like intensity has been done recently. And for shorter events (let’s
say that means less than about 4 hours) what’s the most critical element of the
serious athlete’s race preparation? Race-like intensity. Doing less of it as you approach race day is just the opposite of what's needed.

So the flawed
basic assumption about the philosophy of periodization it’s making is why I say
it’s “wrong-headed.” Standard periodization doesn’t work that way. But it isn’t
necessarily wrong to train the way it suggests – meaning high intensity in Base
and high duration/volume in Build.

If training
for a long event, greater than 4 hours, then race duration becomes more
critical because race intensity is becoming so low that achieving it is not a
big problem. The greater problem is maintaining that low intensity for many,
many hours. So in this case, doing high intensity in Base, especially late
Base, and high duration/volume in Build is exactly what the concept of periodization
intends – the closer to the race you get, the more like the race training
should become.

As it turns
out, Jesper is training for such long events. So using this method is a
reasonable way for him to train. He would make training increasingly like the
race by doing this. So it’s really not “reverse” periodization he’d be doing.

Aging: Designing a Microcycle to Match Your Recovery

Training
dose and density are really all about
recovery. Dose has to do with how great the daily training load is. Density is how
many high-dose workouts you can do in a given period of time, such as a week or
month, while still allowing for recovery in order to avoid the risk of injury
or overtraining.

Besides
individualizing the dose and density of training, your recovery is also largely
determined by certain aspects of your lifestyle such as sleep, nutrition and other
recovery enhancers. I wrote about some of them previously in this series on
aging – here and here. In this post I want to
address how to match your training plan with your rate of recovery.

As
with all things related to recovery – and just about everything else when
talking about aging – we each have unique circumstances. So I won’t be able to
tell you exactly what your dose and density should be. You’ll have to figure
that out for yourself. But I’ll give you help in getting started.

You’ll
recall in my last post here I again proposed that in
order to slow the loss of performance with aging there are two things nearly
all older athletes should focus on – aerobic capacity and strength training.
Both involve high-intensity effort and so require consideration of how many of
each you should do in a training microcycle, such as a week. This brings us to
the topic of periodization.

I’d like to do a quick and dirty review of periodization – relative
to senior athletes, aerobic capacity and strength training – just to make sure
we’re on the same page. Periodization in general is explained in much greater
detail in my Training Bible
and other books. 

A good starting place for this discussion is how long your microcycle should be. A microcycle is
the shortest training period and usually is only a few days long. Seven is the
most common number as that generally fits nicely with a work week. Shorter
workouts can be done Monday through Friday with longer ones on the weekend when
most athletes have more free time. But seven days may not be optimal for most
athletes. In fact, it seldom is if we are only considering your rate of recovery, physiological
capacity for adaptation and fitness enhancement.

If you are retired or don’t have a demanding weekly work schedule,
you may consider changing the number of days in a microcycle to enhance dose
and density. I’ve found that nine is a much better number of days for most
senior athletes. By doing a hard (high-dose) workout (for example, a race-specific workout, aerobic
capacity, lactate threshold or strength training) every third day you then have
two days to recover and be ready for the next one. The two recovery days may include
a day off combined with an easy workout, or cross training (cross training is
especially good for senior runners). Or it could be two easy workouts, or an
easy session in your primary sport plus cross training.

Using a nine-day microcycle your general training routine might
look like this:

Day 1         High dose (race
specificity, aerobic capacity, lactate threshold or strength)

Day 2         Recovery day
(off, easy workout, or cross train)

Day 3         Recovery day

Day 4         High dose

Day 5         Recovery day

Day 6         Recovery day

Day 7         High dose

Day 8         Recovery day

Day 9         Recovery day

Of course, what you do in training is dependent on what period of the
season it is – Prep, Base, Build, Peak, Race or Transition. So consider the
above high-dose days as broad, general suggestions. My Training Bible books address the details of what workouts to do and
when. Also, not every high-dose day should necessarily be the same type of
workout.

Going back to the nine-day microcycle discussed above, an athlete
who is capable of managing greater density may consider making days 3, 6 and/or
9 aerobic endurance (zone 2) or even tempo (zone 3) training days. Or, if three
high-dose sessions in a nine-day microcycle is too challenging (meaning
recovery is inadequate) then one high-dose could be changed to a moderate-dose
(aerobic endurance or tempo) day. It may also be that two recovery days after a
high-dose session aren’t enough for some seniors. In that case it may be
necessary to schedule three after a hard day. Your microcycle could then be four, eight or twelve days long. All of this means that your microcycle is
quite flexible; design it to fit your unique needs.

If you are stuck with a seven-day microcycle due to your work
schedule or other lifestyle determiners then your block may look something like
this:

Day 1         High dose (race
specific, aerobic capacity, lactate threshold or strength)

Day 2         Recovery day
(off, easy workout, or cross train)

Day 3         Recovery day

Day 4         Moderate dose (reduced race specific, aerobic capacity,
lactate threshold or strength)

Day 5         Recovery day

Day 6         Moderate dose
(aerobic endurance – zone 2 or tempo – zone 3)

Day 7         Recovery day

The seven-day microcycle reduces both the dose and density of
training relative to nine days in order to allow for adequate recovery and
therefore reduces the resulting fitness adaptation. Another option of the
seven-day cycle would be to do only two high dose sessions in a week (perhaps
days 1 and 5) thus allowing for five recovery and/or moderate dose workouts.

There are other ways of periodizing the microcycle to fit a given
athlete’s lifestyle constraints and typical recovery rate. With a little
creativity you can come up with something that works even better for you than
what I’ve suggested here. As I’ve mentioned numerous times in this series,
athletes are unique. Do what best matches your individual needs.

In my next post in this series I’ll discuss mesocycle design
relative to the senior athlete's recovery.

This Week's "High" Heart Rate Question

Emailed question:

I'm going to be purchasing your book "The Cyclist's Training Bible", but in the meantime I have a question for you regarding cycling within specific heart rate zones/ranges.

I'm 41 years old and started (recreational) cycling this year, mostly as a means of cardio exercise.  I'm not extremely fit, but have become more fit than I have been for a long time.  I have completed 2 metric century rides and usually try to do one 60-80 km ride once a week and 20-25km rides twice a week prior to heading to the office.
I've noticed that my heart rate is usually in the 165-180 range for most of my ride (many times around 171-175 for quite some time -- at least that's what I usually see when looking at my cyclometer).  I haven't tracked how much variance there is, however, my concern is the possibility of this being too taxing on my heart.  My last couple of rides (30-50km rides), I have tried staying between 150 and 160 bpm just to be safe.
Can being in this range for a long period of time be dangerous?  I notice that I feel that my heart is still racing several hours after a ride (although I have noticed that after stopping and taking off the heart rate monitor shortly after my ride it has already dropped to around 130 or less).
Should there be any reason for concern?  Should I even be monitoring that closely?

My answer:

Let's address this from two different perspectives. The first has to do with "high" heart rate. The second with if your heart is in danger due to exercise.

Heart rate is as variable as shoe size is. There is a bell-shaped curve when it comes to HR. You may simply be at the high end of the curve. I assume you're basing your concern on "220 - your age," which is no more likely to be right than assuming shoe size has a predictive formula based on age. There isn't one HR that is appropriate for every person, for every level of exercise intensity. There is no reason to be concerned about your exercise HR unless you experience the symptoms of heart disease (pressure in chest, radiating pain in neck or arm, weakness or dizziness, nausea, irregular heartbeats, etc). If you experience any of these or feel there is really something unusual about your HR, please see your doctor right away. Here is a blog post Dr. John Post and I wrote on this topic sometime back which may help you understand your exercise HR.  


 As for damage to your heart due to exercise, it's a topic open for debate among experts on the topic. You might read this for both points of view. 

Aging: Risk, Dose and Density

Let’s review some critical points before moving on.

I’ve
been making the point, based on the aging research, that experienced senior
athletes are most likely to improve or maintain their endurance performance by
focusing on aerobic capacity and muscular strength. Such training is high
intensity. That presents the possibility of injury since older athletes are
more “fragile” than they were when younger.

There
isn’t just one way to train, however, that works for all senior athletes. The
research is drawing general conclusions based on a wide sample. Not everyone
has the same needs. The newer you are to your sport, for example, the more
likely you are to improve or maintain your performance by simply putting in
lots of training time. For the experienced athlete such training is of less
value. High intensity is likely to be more beneficial, albeit risky, for these
athletes. There are other considerations besides experience.

Your
unique individual situation must always be considered when designing a training
plan. This should take into account your age, previous training, body weight,
health, sensitivity to training stress, risk of injury, time available for
training, the goal event, training partners and much more. Then there are the
environmental factors where you live and train to consider, such as altitude,
terrain, weather, training venue availability and on and on. Even if aerobic
capacity and strength training are right for you physiologically, some of these
factors may interfere with such training.

Aerobic
capacity training may also not be your limiter. The other determiners of
endurance performance are lactate threshold and economy. Let’s do a quick
review of all three so you can draw a conclusion as to which you most need to
address in your training. The best way to determine your training needs for
each of these is to be tested for VO2max and ask the technician for a comparison of your data relative to other athletes of various ages. Such tests are often available at
medical clinics; universities; health clubs; running, bike and triathlon shops;
and are often offered as a service by coaches. Expect to spend at least US$150
for such a test.

Here
is a very brief summary of each (click on the links to read more details to help
determine what your major limiter may be).

Aerobic capacity (VO2max) – how much oxygen
your body is capable of utilizing at maximal aerobic effort to produce energy.
The higher this is, the greater your potential for high performance. In
experienced athletes, this responds best to workouts that are done at or
slightly below VO2max.
Lactate threshold – at what percentage of
VO2max do you begin to “redline” due to increasing acidity. May also be
referred to by the tester as anaerobic threshold, functional threshold, maximum
lactate steady state, and other names. Be sure to ask for a definition. The
higher the LT percentage is relative to VO2max, the better your endurance
performance is likely to be. An LT between 80 and 90% of VO2max is common in fit athletes of all ages. Again, similar to aerobic capacity, in experienced
athletes the most affective training to elevate LT is to do workouts at or
slightly below LT.
Economy – how efficiently you use
oxygen (a proxy for energy) to produce movement. As economy of movement
improves, you race faster or use less energy at any given submaximal effort.
It’s very difficult to improve economy in highly experienced athletes, but high
intensity has been shown to be effective (Gunnarsson).

In
previous posts (here, here, and here) I’ve discussed these three
endurance performance markers and their likelihood to be at the root of a
performance decline as you get older. I’m of the opinion that a great portion
(most?) of your loss over time is largely due to things you have some degree of
control over.

But back to testing... If
you’d rather not spend the money (I couldn’t blame you) you may just
want to accept that you fit the description of the experienced senior athlete
found in most of the research I’ve been reviewing. In that case you could draw
the conclusion that aerobic capacity is your major limiter and address it in
your training. More than likely, that’s what you would find out through
testing.

So
why not the other two? In the above posts I made the case that economy is
likely not the limiter for most senior athletes as many years of training for a
given sport has a tendency to refine and optimize one’s movement patterns. The
same goes for lactate threshold as it’s been shown to be at a higher percentage
of older athletes’ aerobic capacities than that of young athletes. That leaves
aerobic capacity. Several studies have shown this to be the one we geezers have
the greatest need to improve. It appears to decline for many reasons – some mix
of age- and training-related causes.

Then
there’s the matter of muscle loss that typically comes with aging and may also play a role in the decline of
your race results over a long period of time. Less muscle means less power. And
that means slower speed.

This
brings us back to what can be done to slow the losses, maintain current levels
or even improve aerobic capacity and muscle mass – again, assuming these are
limiters for you. I’ve previously proposed two solutions that both involve
high-intensity training: aerobic capacity intervals (or fartlek, hill reps, hard group workouts, etc) and weight lifting. Heavy
resistance strength training (Vale) and high-intensity aerobic capacity training
(Pritzlaff, Pritzlaff) have been shown to stimulate the production of anabolic
hormones – such as testosterone, estrogen, growth hormone and insulin-like
growth factor – at a greater rate than low-intensity training while also being
more effective for performance gains in well-trained athletes (Laursen). Such
hormones build and remodel the tissues necessary for improvements in your
aerobic capacity and muscle strength. They keep you "young."

Let’s again take a look at the risk associated with such training. High-intensity training
increases the possibility of injury due to great stress. So if you are to train
as I’m proposing here, some how you must decrease the risk. The way to do this
is to be both cautious with training load starting points, and conservative
with their increases. This comes down to what sport scientists call “dose” and
“density.”

Dose has to do with how hard a
given workout is – its duration and intensity. Duration may not be a problem
for you (although it often is for runners who may need to consider cross training on easy, recovery days). Most senior athletes I’ve known have gravitated toward doing long, rather
slow workouts. If you’re like most senior athletes, high intensity likely gets
little attention in your workouts which further increases your chances of an
injury if you bump up the training zones suddenly. To keep your risk of injury
manageable it’s important that you be conservative with high-intensity
workloads, especially when doing workouts such as aerobic capacity intervals
and heavy resistance training. That means knowing what your limits are and
staying well below them. Stop the interval session when you know you have one or
two good reps left in you. Don’t try to beat your 1-repetition max in the
weight room on your last set.

That’s
dose. Let’s examine density.

Density describes how frequently you
do these risky workouts. The more frequent the challenging workouts are done, the
greater the density and the higher your risk. Allow plenty of time between hard
sessions. When you first start training this way that may mean one such workout
in a week. That gives you six days of low-intensity to fully recover. As the
season progresses and your body slowly adapts, you may be able to make these workouts more dense,
meaning fewer recovery days between them. The older you are, the less dense
your training should probably be. A 50-year-old can typically handle more
density than a 70-year-old. The same goes for dose.

For triathletes this does not mean do multiple high-intensity aerobic capacity sessions in each sport. A senior triathlete when first starting such a training regimen may only do one such workout for the entire week. It's then best to use it for your weakest sport. Over time, more aerobic capacity sessions may be added to the week. The triathlete must also consider the risk associated with such training in each sport. For example, high-intensity swim training has a lower dose-density risk than running.

The bottom line for both dose and density is
this: Seldom try to find your limits. Instead, slowly “push them higher from
the bottom up.” Do not “pull them up from the top.” That means, don’t force your body to adapt with
excessively high dose and density. Instead, allow it to adapt slowly. Be
cautious and conservative. Restrict both the volume of high intensity and its
frequency. Train within your known limits. So what does that mean? This has to do with training periodization for
senior athletes, which I’ll get into in my next post.

References

Gunnarsson TP, Christensen PM, Holse
K, et al. 2012. Effect of additional
speed endurance training on performance and muscle adaptations. Med Sci Sports
Exerc 44(10):1942-8.

Laursen PB. 2010. Training for intense exercise performance:
high-intensity or high-volume training? Scand J Med Sci Sports 20 Suppl 2:1-10.

Pritzlaff CJ, Wideman L, Weltman JY,
et al. 1999. Impact of acute
exercise intensity on pulsatile growth hormone release in men. J Appl Physiol 87(2):498-504.

Pritzlaff CJ, Wideman L, Blumer J,
et al. 2000. Catecholamine release,
growth hormone secretion, and energy expenditure during exercise vs. recovery
in men. J
Appl Physiol 89(3):937-46.

Vale RG, de Oliveira RD, Pernambuco
CS, et al. 2009. Effects of
muscle strength and aerobic training on basal serum levels of IGF-1 and
cortisol in elderly women. Arch Gerontol Geriatr
49(3):343-7.