Not many things make me want to punch myself in the face more than watching guys at the gym doing four million crunches, all the while thinking that they are somehow magically “sculpting, toning and defining” their midsections. Let me be clear when I say I am not badmouthing crunches as a standalone exercise; I’ll be the first to tell you that every exercise you can possibly do—as well as every combination of reps and sets—can prove valuable for the right reasons. Problems arise when the exercises a person performs do not match up with their goals. At that point, you’ve got a waste of time.
In the crunches example, I am referencing the rectus abdominus muscles of the core, or what we all call a “six-pack.” Most people want to be able to see these muscles and, typically, that means the person needs to lose some of the layer of subcutaneous body fat that is covering up their hidden six-pack. In this case, the goal is straightforward and the thing that needs to be changed is also obvious (lose body fat.) The problem arises when a person attempts to make the fat layer covering their ab muscles disappear by working the underlying muscles with crunches, side bends, or some other exercise that works only the local musculature. Why doesn’t this work? I’ll explain using a car metaphor.
Your car has a brake pedal and a gas pedal and they are located right next to each other. No matter how hard you push on the gas pedal, it won’t stop your car as you zing along the freeway at top speed. The same thing can be said about the fact that pumping the brakes with all of your might, will never make the car speed up. These two pedals are very close in proximity but very divergent in function. The same thing is true of your abdominal muscles and the fat layer over top of them. Working out your six pack muscles will NEVER have any direct effect on the fat covering it up, no matter how much you want to believe that it will. Just because they are located in the same area, doesn’t meant they have any interrelationship at all.
As if that wasn’t bad enough news, I have an even worse piece of information for you: While there is no such thing as spot reduction, there is such thing as spot increase. You know those hanging leg raises you have been doing? Yeah, there is a pretty good chance that you have been doing them with enough gusto that you have stimulated your abdominal muscles to get BIGGER through a process known as hypertrophy. Working any of the muscles on your body hard enough will result in them adapting to the challenges of those workouts by becoming not only stronger, but larger. That’s right; not only did you fail at peeling the fat off of your midsection but you may have made your waist larger. Oops.
Most exercise plans are based on one side of the spectrum or the other. Higher intensity with lower volume or lower intensity with higher volume. Each of these types of exercise plans yields very different results. If strength adaptations are your goal, make sure to stick with the higher intensity, lower volume end of the spectrum, but if you are looking for larger muscles science tells us that the lower intensity and higher volume approach is better suited for your goal. What this means for those of you out there that might be looking to shed a few pounds of fat, is that the heavy weights are your friends, not your foe.
If we now go back to our example of a person doing crunches by the bunches and you apply the aforementioned understanding that doing a lot of lower intensity resistance exercises will typically result in muscle hypertrophy (size increase,) you can begin to see why unless you want a larger midsection, this might not be the way to go.
First, I told you that there is no such thing as spot reduction and now I give you a better understanding that not only do light weights with high reps NOT make you more ripped, but in fact this type of training will INCREASE the size of a muscle, thereby pushing out the fat that you currently have even further. Talk about being the bearer of bad news! So, what’s the solve here? Well, there are lots of ways to approach the fat-loss conundrum including controlling your food intake and increasing your total calorie expenditure with things like high intensity interval training (HIIT). There is no quick fix when it comes to fat loss, but at least now you won’t be wasting time trying to spot reduce when it’s not possible or being confused about the amount of weight you use in your resistance training routine. High intensity exercise using heavy weights is great for ridding your whole body of excess fat, so stop messing around and pick up something heavy!