By Kenneth Muir (Contributor) – Email
Print Edition: March 7, 2012
As I’ve alluded to in previous articles, there are numerous factors that affect the amount of progress one can extract out of a workout. Working at the right intensity level, for instance, will help you to train your body to do specific things. Staying hydrated will allow you to work at those intensities with less effort. Working out consistently will get you fit faster and will keep you motivated. Theoretically, if you tailor all of these factors correctly, you should be able to maximize the gains from your workouts, and achieve your goals even faster. Of course, there are a rather large number of factors to consider, but most of them can be controlled. This week, we’ll be discussing the effects of sleep, or more specifically, a lack of.
A common misconception is that working out is what grows muscle. At first glance, it certainly appears so: during and after your workout, your body’s muscle groups are tight, which causes them to look larger than they normally are. What workouts actually do is cause light damage to muscle tissue. Exerting enough effort causes micro-tears in your muscles, weakening their overall ability to do work. By working out, we’re actually in the practice of attacking our own bodies.
These micro-tears stimulate your body to repair the damage and to increase the number of cells devoted to the muscle, in an effort to stop more micro-tears from forming if similar stresses are faced in the future. In this manner, your body repairs the damage caused by a workout, and then strengthens the area. Most of this repair and growth, however, occurs in your sleep.
Dr. Eve Van Cauter from the University of Chicago conducted a study in which healthy males in their 20s slept eight hours a night for four nights, then four hours a night for six nights, and then finally 12 hours a night for seven nights. He discovered that after his subjects had slept for four hours a night for six nights, the subjects had higher stress hormone levels, could not efficiently metabolize glucose, and had diminished levels of human growth hormone.
The inability to properly metabolize glucose means that the body won’t be able to produce glycogen, which is the main energy source for muscles. This means that if you completed a workout, slept for four hours, and then tried to do another workout the next day, your muscles would have virtually no energy reserves. Your workout quality would dive-bomb. The lower levels of growth hormone would mean that your body would be less able to devote more cells to your damaged muscles. Your workout would become worthless if you’re sleep deprived, because your body has no way of increasing the amount of muscle. Finally, stress hormones sometimes interfere with the body’s ability to repair damaged muscle, so an increase of stress hormones would cause your body to still feel weakened by your previous workout, as it hadn’t been properly repaired.
Overall, not sleeping enough is extremely debilitating to the amount of progress you can achieve by working out. In another, similar study, Dr. Eve Van Cauter found that sleep deprivation also caused increases in hunger and appetite, which could lead to overeating.
The clear way to avoid these problems is to sleep enough and sleep regularly. It’s rather difficult to sleep too much, so sleep in excess wherever possible. As students, it’s often tempting to pull all-nighters in order to study for exams, or finish an essay the night before they’re due. Do try to avoid getting into those situations in the first place; your workout will dearly suffer for it.