Lifting Weights While Fasting

You might want to take a break from weightlifting if you're fasting.

You might want to take a break from weightlifting if you're fasting.

Lifting weights while fasting? Even if your 10th high school reunion is coming up and you want to drop a few pounds while toning up to impress former classmates, it's hardly worth torturing yourself -- especially since it's unlikely to work. However, the question of fasting and exercise is more complex than it sounds; some experts say intermittent fasts might actually be good for you.


There are many types of fasts, from religious fasts to intermittent fasts, from one day a week to detox fasts that require you to fast for a time and then limit you to a combination of juices, vegetables, fruit and perhaps herbs. The more severe and lengthy the fast, the less energy you'll have to lift or exercise. Detox fasts and diets, for example, often cause fatigue and sometimes cause dehydration, says Under those circumstances, pumping iron will not be effective and might even be dangerous.

Lifting While Fasting states "intense physical training while fasting is not recommended." That's because lifting damages and tears down muscles. You need protein to build back muscle tissue during the normal recovery and rebuilding phase. But you won't be consuming any protein during a fast, so lifting can result in the weakening of muscles. "The Times of India" recommends that people who fast from sunup to sundown during Ramadan refrain from lifting and heavy exercise during fasting hours, citing the effects of muscle breakdown, a rise in cortisol level and possible dehydration. But after sunset and before sunrise, when your body is refueled, lifting is fine.

Intermittent Fasting

If you're going to fast, intermittent fasting seems like the best way to go. Mark P. Mattson, chief of the laboratory of neurosciences at the National Institute on Aging, has studied fasting, and says a once-a-week fast or a twice-weekly food cutback "will have health benefits for most anybody." Some research indicates that moderate amounts of fasting is associated with better heart health, improved mental health and longer life. Other experts think intermittent fasting is a recipe for disaster. "You're hungry, fatigued, irritable," dietitian Ruth Frechman told the "Los Angeles Times." "Fasting is not very comfortable. People try to cut back one day and the next day they're starving and they overeat."


While lifting during a fast is unlikely to be productive, other exercise during an intermittent fast or a Ramadan-type fast period seems to be fine. Research published in the "Saudi Medical Journal," conducted on a group of sedentary men, concluded there was no significant downside to moderate cardio exercise during the fasting daylight hours. Since there are so many types of fasts, you'll want to consult your doctor or trainer to make sure you're acting in a safe and effective way if you intend to mix fasting with lifting or other exercise.

About the Author

Jim Thomas has been a freelance writer since 1978. He wrote a book about professional golfers and has written magazine articles about sports, politics, legal issues, travel and business for national and Northwest publications. He received a Juris Doctor from Duke Law School and a Bachelor of Science in political science from Whitman College.

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