Professional boxers don't rely on punching alone to sculpt their bodies.
Ethan Miller/Getty Images Sport/Getty Images
Taking a punch may look like it's exclusively an upper-body movement to the naked eye, but to throw a punch with speed and power, you need to incorporate your entire body into the motion. Your core muscles, including your abdominals, help you derive speed and power by allowing you to twist into each punch with real torque. Hitting a punching bag can help you burn calories and develop your abs.
Your triceps, deltoids and upper back muscles are all important for extending and retracting punches, but the real power comes from your lower body and core muscles, including your abs. If you throw a punch with proper technique, you should hold your breath, tighten your abs and then twist into the strike, exhaling as you extend your punch. The faster and more powerful the motion, the more torque your abs experience, helping them get stronger as you burn a substantial number of calories.
Types of Bags
There are a few different types of punching bags out there, but some are better for developing your abs than others. A speed bag, which is a tear drop-shaped bag that hangs on a board around head level, is not ideal because it doesn't require you to load up on your punches. Heavy bags, on the other hand, are the best punching bags for getting real torque into your strikes. You can throw any type of punch or combination of punches against a heavy bag from all angles, exhausting yourself with an intense workout if you're up to it.
A straight jab off the lead hand recruits your abs, but not to the same degree as punches with more twist to them. A rear-hand cross gets you to pivot on your rear foot, twisting into the punch as you extend across your body. But the two best punches for developing your abs are hooks and uppercuts. Hooks are delivered horizontally across the body, forcing you to pivot hard to the right or left. They isolate your upper body more than your lower body. Uppercuts force you to duck down and then explode up with your core muscles to deliver the strike.
Muscles are built more effectively in the anaerobic training zone than in the aerobic training zone. The more intense your workout, the faster your heart beats; the faster your heart beats, the more muscle you can build. To enter the anaerobic zone when punching a bag, your heart rate must exceed 80 percent of its maximum. But for an ideal, lengthy workout, you should alternate between fast punches and slower, more methodical aerobic combinations, where oxygen is your main energy source. Muscles regenerate when satellite cells are activated due to microscopic tissue damage, which occurs with the sharp twisting and recoil forces your abs experience unloading on the heavy bag. To focus the workout on your abs, concentrate on twisting into each punch, and throw hooks and uppercuts more often than jabs and crosses. Additionally, burning a large number of calories will help your abs become more visible by reducing the amount of fat around your muscles.