Lighter Weights with More Reps Are Effective for Building Muscle
A well-rounded fitness routine includes both cardiovascular exercises and strength training. However, most women tend to shy away from weights, mistakenly thinking that they are only for body builders. Studies from McMaster University reinforce the benefits of strength training for women, plus break a long-held misconception about using lighter weights.
According to the National Center for Health Statistics, only 21% of women strength-train two or more times per week. Unfortunately, those women who skip the weight room are missing an incredible opportunity for ultimate fat-burning potential. Just two sessions per week can reduce overall body fat by about 3 percentage points (equal to three inches off the weight and hips) in just 10 weeks, even with no change to the diet.
But you don’t need to bench press as much as an NFL football player to see great results!
Cam Mitchell, a PhD candidate in the Department of Kinesiology at McMaster, has found that whether using light weights or heavy weights, the key to building muscle is working to the point of fatigue. For the study published in the Journal of Applied Physiology, Mitchell and colleagues conducted a series of experiments on healthy, young male volunteers. Each subject was assigned to a leg training program in one of the following combinations: one set at 80% of maximum load, three sets at 80% of the max, and three sets at 30% of maximum.
After 10 weeks, those training with three sets of either heavy or light weights saw significant gains in muscle volume when measured by MRI. The group using heavier weights developed a bit more strength, but essentially working to fatigue showed the greatest increase in muscle size.
Stuart Phillips, supervisor of the study, said, “Our study provides evidence for a simpler paradigm, where a much broader range of loads including quite light loads can induce muscle growth, provided it is lifted to the point where it is difficult to maintain good form. We're convinced that growing muscle means stimulating your muscle to make new muscle proteins, a process in the body that over time accumulates into bigger muscles”
This study builds on others that have been conducted at McMaster’s Department of Kinesiology over the past few years. PhD student Nicholas Burd says, "These findings have important implications from a public health standpoint because skeletal muscle mass is a large contributor to daily energy expenditure and it assists in weight management. Additionally, skeletal muscle mass, because of its overall size, is the primary site of blood sugar disposal and thus will likely play a role in reducing the risk for development of type II diabetes."
To get started with weight lifting, women are encouraged to visit the Discovery Health website where more than 40 exercises are demonstrated using easy-to-follow steps and helpful photos.
C. J. Mitchell, T. A. Churchward-Venne, D. D. W. West, N. A. Burd, L. Breen, S. K. Baker, S. M. Phillips. Resistance exercise load does not determine training-mediated hypertrophic gains in young men. Journal of Applied Physiology, 2012; DOI: 10.1152/japplphysiol.00307.2012
Nicholas A. Burd, Cameron J. Mitchell, Tyler A. Churchward-Venne, Stuart M. Phillips. Bigger weights may not beget bigger muscles: evidence from acute muscle protein synthetic responses after resistance exercise. Applied Physiology, Nutrition, and Metabolism, 2012 DOI: 10.1139/h2012-022
Burd et al. Low-Load High Volume Resistance Exercise Stimulates Muscle Protein Synthesis More Than High-Load Low Volume Resistance Exercise in Young Men.PLoS ONE, 2010; 5 (8): e12033 DOI:10.1371/journal.pone.0012033