
When it comes to weight loss, diet is much more influential than exercise. It’s a truth I denied for many years. In my late twenties I became very active and lost weight and fortunately, incorporated exercise, both cardio and weight-bearing, into my daily routine. As often happens, I eventually plateaued, and my weight loss stopped. I always hoped that I could exercise enough to be able to eat whatever I wanted. Turns out the opposite is true: If you eat properly, you can exercise less. I recently discovered intermittent fasting, and after about a year, I think it’s safe to say that this is a way of life for me.
Simply stated, fasting is going without food or flavored beverages for a period of time. Black coffee and water are two of the limited number of beverages that will not “break” your fast. It’s important to note that fasting has many benefits in addition to weight loss. The basic premise is that while in a fasted state, our bodies not only go into “fat burning” mode, but also “cell repair” mode, which causes your body to use stored energy to clean up damaged cells and expel damaged cells and toxins from your body. In addition, fasting can reduce inflammation, improve digestive health, heart health, and brain health, all of which will help prevent disease and contribute to better overrall health as you age. Fasting doesn’t cost anything, requires no equipment, and is easy to incorporate into any lifestyle because you pick when–and how long–you fast. For more information on fasting, check out some of the books by Gin Stephens, Jason Fung, or James Clement.
Exercise is also important for many reasons that don’t include slimming down. Regular exercise can improve your mood and energy, improve sleep, and reduce or eliminate risks for many ailments including high blood pressure, diabetes, depression, arthritis, and some types of cancer. As always, talk to your doctor before beginning a new diet or exercise plan, particularly if you have a chronic health condition like low blood pressure, asthma, or joint pain.
So fasting and exercise can both be very beneficial to your health. The question I’m asking today is, will exercising while fasting improve my success rate when it comes to weight loss?
Working out during your fasting period has been shown to multiply your fat burning efforts. Research shows this number may be as high as a 20 percent increase. When exercising in a fasted state, your body has no choice but to burn calories in stored fat, rather than in food you’ve recently eaten. Insulin is the magic component that causes your body to gain weight. Both fasting, and exercising, can drive that number down. So it makes sense that combining the two will exponentially improve those results. The benefits are present in both cardio exercises and strength training exercises.
In one recent study, all the participants ate junk food every day. Some of the participants exercised after eating breakfast. They still gained weight. Another group exercised during a fasting period and gained no weight, even with the same bad diet. The benefits may be less valuable for certain types of individuals. Other studies have shown that working out during a fasting period may affect performance negatively, and may affect how well your body builds muscle, so fasted exercise may not be best for endurance athletes, or those trying to build larger muscles.
If you’re new to fasting, it is suggested that you get your body used to a fasted state before doing more intense workouts. Build up by starting with walking or cycling. And always drink plenty of water. This is important with both fasting and exercising. The diet you choose during your “eating window,” (the period when you are not fasting), will also affect your results. It’s always good to avoid sugar and simple carbohydrates, focusing more on complex carbohydrates like vegetables, beans, and whole grains. Be sure to get enough protein and healthy fats like avocado, nuts, seeds, and olive oil.
But for most of us who have incorporated either fasting, or exercising into our daily routines, it is likely safe, and in most cases beneficial to weight loss, to incorporate both of these activities at the same time.