Bodytalk
Question: If I have to take some time off from exercise, how long will it take me to lose my aerobic and strength fitness? Fitness loss occurs
at a rapid paceAnswer: It doesn't seem fair, but the fitter you are, the faster you lose the benefits of regular exercise. On the other hand, fitter people can afford to lose a lot more than the less fit.
Loss of fitness occurs the fastest during the first three weeks of down time.
Exercise challenges the body and it responds by adapting to meet the challenge. When you discontinue your workouts, your body responds by adapting back down to the lower level of challenge you're placing on it.
In the absence of exercise, the psychological effects of regular exercise begin to wane almost immediately. This happens because during exercise the body produces hormones such as adrenaline and endorphins. These substances are mood elevators. Unfortunately, it takes just a couple of days of slacking for these mood enhancing substances to start dropping.
After a couple more days of inactivity, sleep patterns become interrupted.
Next, your ability to concentrate becomes impaired and your attention span shortens.
The next time you can't sleep, are feeling glum, or are having difficulty concentrating, start going for vigorous walks or jogs daily. Then notice how much better your outlook on life is, how much more restful your sleep becomes, and how much more mental energy you can muster for the important things in your life. These payoffs are immediate.
IT'S not until around day nine that the physical body begins to feel the lack of exercise. At this point, your muscles start feeling tight from disuse. Your flexibility decreases and stretching can even be painful.
Next, your maximum heart rate and cardiac output start to fall. This slide starts at around day twelve. Your body's ability to perform endurance exercise, such as cycling and jogging, declines by approximately 15 percent.
The enzymes that are used by your body to produce energy dwindle, and your blood volume drops by up to 15 percent as well. This means you can't deliver oxygen to your muscles as quickly and you begin to feel sluggish. Also at day 12, the body's VO2 max - its ability to utilize the oxygen that is delivered to the body's tissues - can fall by as much as 7 percent.
After just eight more days of added inactivity, you can expect your VO2 max to have dropped by as much as 20 percent, and you may feel breathless after walking up a flight of stairs. In another day or two, your body becomes less efficient at sweating and ridding itself of heat.
If you continue down this road of deconditioning for 6 to 8 months, practically all the benefits you've gained from your aerobic training will be lost.
The picture isn't quite as bleak when it comes to muscular fitness.
Muscular strength and the muscles' ability to perform break down at a much slower rate. It takes about three weeks of deconditioning before there's a noticeable decline in muscle strength. But if you avoid those free weights for 35 days, your muscles will atrophy by about 20 percent.
Fortunately for both the endurance athlete and the weight lifter, it's easier the second time around. In fact, it takes only about six weeks of serious training for weight lifters to regain the muscle mass they had at their peak. Endurance athletes will need approximately two weeks of serious training for every week off, in order to get back up to their personal best.
Health Events
Stephenie Karony is a certified health
and fitness instructor, a personal trainer and the author of
"Body Shaping with Free Weights." Send questions to her at
P.O. Box 262, Wailuku Hi. Her column appears on Wednesdays.