In the last post we learned how sprinting and endurance weight training can help keep a runner from eating his/her own muscle (which can occur from the release of cortisol during long slow runs). There’s also another benefit of speed work and resistance training. Both boost your metabolism which means increased calorie burn. If you burn more calories than you’re taking in, then guess what? You’ll lose weight.
In order to lose a pound of fat in a week, you need to decrease your calorie intake by 3,500 calories weekly (~500cals a day). This can be done by eating less, but it can also be done by burning more calories. Exercise and watching what you eat go hand-in-hand and this combination is the best way to lose weight. It may not be ultra fast, but it will work.
Now be careful not to fall back into the trap of thinking that running will do all the work for you. Remember, the best way to get a good calorie burn is by doing some type of speed work mixed in with your regular weekly runs. Slow steady running (with no other form of exercise) is going to release that bad old cortisol which can eat away at your own muscle. With less muscle, you’ll burn fewer calories which all allow that fat to creep back on you.
Now initially with regular steady running, you may see some weight loss, but unfortunately a lot of that may be muscle loss not fat loss. Slow steady running and not eating can also cause you to gain weight. Have you ever tried to lose weight by just not eating, but instead of losing weight you gain? Your body needs fat to survive. The protective covering (myelin sheath) around your nerves is actually made of fat. If you suddenly stop eating, your body thinks it’s starving and will go into a self-preservation mode. Normally, if you run out of carbs, your body will turn to fat stores for energy, but if your body feels it is starving it will preserve the fat by using muscle tissue for energy. Your muscles are little calorie-burning engines. If you have less muscle tissue, those engines aren't going to be working as hard and your metabolism slows down. This decrease in caloric burn can actually cause weight gain. Can see a viscous cycle happening? If you’ve ever watched The Biggest Loser, one common thread you hear over and over is that “you have to eat to lose weight.” You can’t just eat anything, but if you’re working out while you’re trying to lose weight, you have to remember that you have to fuel and refuel your muscles before and after a workout.
Resistance training also has an added benefit to weight loss. Studies have shown that once you stop running, the extra calorie burn pretty much stops too. Weight training, however, has shown that the calorie burn actually continues for 9 or more hours after completing the workout. So, you continue to burn more calories even after your workout. Sweet!
All of this information does not mean, “Don’t run.” It simply means, “Don’t just run.” In order to keep you a healthy runner and promote muscle growth and regeneration as well as keep your metabolism ramped up, and main your weight (or even lose some), you need to mix it up with speed work and resistance training.