Train with heavy loads to burn more energy and lose fat to get lean for summer. Strength training with heavy loads above 70 percent of your maximal lift for any exercise is best for helping you get strong and lean because it causes a significant afterburn effect so that your body is using more energy after you are finished working out.
A new study in the journal Applied Physiology, Nutrition and Metabolism compared the amount of energy burned during and following two sets to failure of the bench press using three different loads (70, 80, or 90 percent of the 1RM). Naturally, the greatest amount of work was completed when the participants used a 70 percent load since they were able to perform significantly more repetitions during both sets due to the lighter load. The 90 percent load produced the least work, but the excess post oxygen consumption (EPOC), which is the amount of energy burned after training, was nearly equal across all three loads.
EPOC is a valuable measure of the effectiveness of a protocol because it means the metabolism is elevated to a significant degree after the exercise bout, and you continue burning a larger volume of calories than at rest. EPOC is elevated much more after exercise that uses the anaerobic than the aerobic energy system, which is the reason that high-intensity intervals and strength training are best for fat loss.
The results of this study show how EPOC is primarily contingent on the intensity of your workout rather than volume. Obviously, a higher volume will burn more energy during the workout session, especially if it is at a relatively high intensity (research suggests above 70 percent of maximal will burn the most calories during and after the workout).
But, this study shows that heavy lifting at 90 percent of the 1RM is an extremely good “bang for your buck” intensity because you get the same afterburn as lighter intensities that require more repetitions to produce similar EPOC. Additionally, heavy lifting will make you stronger and recruit higher threshold motor units, and who doesn’t want to be strong?
Take away the understanding that if you or your clients want to lose weight, you must train the anaerobic energy system by using a high intensity. Program training sessions so that you incorporate workouts with a high volume and moderately heavy intensity (70 to 80 percent of the 1RM) as well as days when you train a lower volume and very heavy loads (90 plus percent). You’ll get the valuable increase in EPOC after workouts, while using significant energy during workouts. Loads of 70 to 80 percent will build muscle since they trigger hypertrophy more than the near maximal loads, which will make you strong.
Scott, C., Leary, M., et al. Energy Expenditure Characteristics of Weight Lifting: 2 Sets to Fatigue. Applied, Physiology, Nutrition, and Metabolism. 2011. 115-120.