Fasting involves freely abstaining from food and/or drinks for set periods.
People may fast for health, religious, or cultural reasons.
Fasting windows can last from several hours a day to a few weeks.

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As fasting has become more widespread, there is more interest in the effects of merging fasting and exercise.
Research shows that fasting workouts may enhance weight loss and other benefits of fasting.
However, the adverse effects of exercising on an empty stomach may affect the results of your workouts.
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What Is Considered Fasting?
It focuses on when to eat food, rather than what you eat.
Working out while intermittent fasting ideally happens when you have the most hydration in your body.
Can You Exercise During a Religious Fast?
Working out upon waking, or shortly after, supports your body’s natural circadian rhythm.
Working out too close to your bedtime can interfere with deep and REM sleep.
This can increase your risk of dehydration because the level of fluids in your body is less than ideal.
Listen to your body and the signals it may send telling you to stop and rest during your workout.
Elevated sweat rates and inadequate fluid intake can lead to a state of dehydration or exercise-relatedheat exhaustion.
Avoid excessive sugar, calories, fats, and carbohydrates.
Better options for breaking your fast involve foods that are gentle on your digestive system and provide essential nutrients.
Blending these two practices may help you lose weight.
However, it is unclear whether doing so is any better than calorie-restricted eating.
Working out while fasting may help you reach this point faster.
Though it may have benefits, it may also cause harm to people with certain health issues.
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