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Maggie had nearly all the signs of overtraining syndrome, an unofficial diagnosis that is characterized by sleep changes, fatigue, moodiness, vulnerability to illness, and physical pain.
TWO PILLS Let’s pretend you’re at a drugstore of the future. You consult with the pharmacist, who gives you a choice between two pills. You point to the first one and ask what it does. The pharmacist ticks the benefits off on her fingers. “Lowers your blood pressure, stabilizes your insulin levels, improves your mood, increases your calorie burn, fights osteoporosis, and cuts your risk of stroke and heart disease. Unfortunately, its side effects include insomnia, skin rash, heart problems, nausea, gas, diarrhea, weight gain, and lots of others.” “Hmmm,” you say. “How about the second pill?
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People who exercise spend less time in the toxic state known as oxidative stress. This noxious condition begins with a free radical, a molecule that is missing an electron. A free radical is rickety, unstable, incomplete. It craves the missing electron, so it swipes one from another molecule—which is now unstable itself and needs to steal a replacement electron of its own. Like a dark mood that is passed from one person to another, each person feeling a little better the bad feelings are dumped onto someone else, oxidative stress is a state that can shear through a cell’s molecular population.
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In an ideal situation, your cells have enough antioxidants to keep up with the need to neutralize free radicals in your body. Free radicals will never be completely eradicated from our bodies. They are continuously being made by the very processes of life—they occur normally through metabolism. In fact, very small numbers of free radicals are important for the normal communication processes in our cells.
when you have more free radicals than antioxidants, you enter an imbalanced state of oxidative stress.
When you exercise regularly, the cells in your adrenal cortex (located inside your adrenal glands) release less cortisol, the notorious stress hormone. With less cortisol, you feel calmer. With regular exercise, cells throughout your body become more sensitive to insulin, which means your blood sugar is more stable. If you want to avoid the common midlife trifecta of stress, belly weight gain, and high blood sugar, you need to exercise.
Exercise helps protect your cells by warding off inflammation and immunosenescence.
exercise helps you maintain your telomeres.
studies have found that sedentary people have shorter telomeres than people who are even a little more active.
Moderate aerobic endurance exercise, performed three times a week for forty-five minutes at a time, for six months, increased telomerase activity twofold. So did high-intensity interval training (HIIT), in which short bursts of heart-pounding activity are alternated with periods of recovery. Resistance exercise had no significant effect on telomerase activity
those who increased their aerobic fitness the most had greater increases in telomerase activity.
In a study of thousands of Americans, the more categories of exercise—from walking to biking to strength training—that people engaged in, the longer their telomeres.
exercise switches on autophagy, the housekeeping activity in the cell that eats up those damaged molecules and recycles them.
Exercise releases a newly identified hormone, irisin, that boosts metabolism and in one study was associated with longer telomeres.
Exercise causes a brief stress response, which triggers an even bigger restorative response.
Later in the same exercise session, when there are too many damaged molecules, and autophagy can no longer keep them under control, the cell dies a quick death (called apoptosis),
For telomere health, you need to get regular exercise and you need to be fit.
One remarkable study of ultrarunners found that their cells were the equivalent of sixteen years younger than those of their sedentary counterparts.
When endurance athletes are compared to more ordinary runners, who might run around ten miles a week, you find that both groups have nice, healthy telomeres compared to the more sedentary group—and that there appears to be no additional benefit for the ultra-long-distance endurance group in terms of telomeres.
One study of extreme exercisers found that they had shorter muscle telomere length—but only if the exercisers suffered from a fatigue-overtraining syndrome.
It appears to be overtraining, not extreme exercise, that is damaging to telomeres, at least in the muscle cells.
Some warning signs of overtraining include fatigue, moodiness, irritability, trouble sleeping, and susceptibility to injuries and illness.
Yet it turns out that the most important time to exercise is exactly when you might not want to—when you are feeling overwhelmed. Exercise can improve your mood for up to three hours after working out20
Women high on perceived stress had shorter telomeres, but only if they were relatively sedentary. If they exercised, they did not show the stress-telomere relationship.
If you have a high-stress life, exercise is not just good for you. It is essential. It protects you from stress-shortened telomeres.
according to the National Sleep Foundation’s 2014 Sleep Health Index, 45 percent of Americans say that poor or insufficient sleep affected their daily activities at least once in the last week.
Chronic insomnia is associated with shorter telomeres, particularly for people over seventy years old
in a brain structure known as the suprachiasmatic nucleus, or SCN.3 A structure of a mere fifty thousand cells, the SCN snuggles like a tiny egg within the larger nest of the brain’s hypothalamus. Don’t be fooled by its size, because the SCN is incredibly important. It’s your body’s central internal clock. It tells you when to feel tired, when to feel alert, and when to get hungry. It also drives the nightly task of cellular housekeeping, when damaged parts are swept away and DNA is repaired.4 When your SCN is working well, you’ll have more energy when you need it, deeper rest at night, and
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Your body also depends on deep, restorative REM sleep to regulate your appetite. (REM sleep is characterized by rapid eye movements, higher heart rate, faster breathing, and more dreaming.) During REM sleep, cortisol is suppressed, and your metabolic rate increases. When you don’t sleep well, you get less REM in the second half
of the night, and that results in higher levels of cortisol and insulin, which stimulate appetite and lead to greater insulin resistance. In plain terms, this means that a bad night of sleep can throw you into a temporary prediabetic state. Studies have shown that even one night of partial sleep, or one night without enough REM sleep, can lead to elevated cortisol the next afternoon or evening, along with changes in the hormones and peptides that regulate appetite and lead to greater feelings of hunger.
sleep itself creates new connections between brain cells, which means that you’re both learning and stabilizing your memory of what you’ve learned.
Sleep deprivation makes all emotions more intense.
Getting at least seven hours of sleep or more is associated with longer telomeres, especially if you are older.
If you feel sleepy during the day, you need more sleep at night.
Good sleep quality also protects the telomeres in your immune system’s CD8 cells. When these cells are young, they attack viruses, bacteria, and other foreign invaders.
people with shorter telomeres in CD8 cells are more likely to catch a cold virus.
excessive daytime sleepiness was also a predictor of shorter telomere length.
Keeping a good sleep-wake rhythm—going to bed and waking up at regular times—may be critical to your cells’ ability to regulate telomerase.
Cognitive behavioral therapy is the best known treatment for insomnia so far, as it challenges your thoughts about insomnia.
In a study by sleep researcher Charles Czeisler and colleagues, people who used an e-reader immediately before bed released around 50 percent less melatonin than people who read from a print book.17 The people using an e-reader took longer to fall asleep, had less REM sleep, and felt less alert in the morning.
Try to avoid screens for an hour before bedtime.
Most sleep loss is caused by “voluntary sleep curtailment,” otherwise known as sleep procrastination, otherwise known as not getting yourself into bed early enough.
More time spent snoring is also linked to telomere shortness,
sometimes sleep is a group project. We have to support one another in reducing sleep procrastination, in going to bed earlier, in not doing business late at night.
Try making your own blend of herbal tea from chamomile, lavender, rose petals, and a slice of fresh lemon or ginger.
Does eating too much shorten your telomeres? The quick and easy answer is yes. The effect of excess weight on telomeres is real—but
Yet being overweight (and not obese) is, surprisingly, not linked strongly to shorter telomeres (nor is it strongly linked to mortality).
in the muscle) is different and maybe even protective, while fat stored deep inside, in the belly, liver, or muscles, is the real underlying threat.
When we say a person has poor metabolic health, we generally mean that he or she has a package of risk factors: belly fat, abnormal cholesterol levels, high blood pressure, and insulin resistance.
Diabetes is a global public health emergency.
