A research study out this week indicates type II muscle mass associated with strength training not only helps reduce body fat but alters overall metabolism.
Researchers from the Boston University School of Medicine (BUSM) have demonstrated that in mice, the use of barbells may be as important to losing weight and improving health as the use of running shoes. The discovery builds upon the fact that skeletal muscle consists of two types of fibers. Endurance training such as running increases the amount of type I muscle fibers, while resistance training such as weightlifting increases type II muscle fibers. Using a mouse genetic model, BUSM researchers demonstrated that an increase in type II muscle mass can reduce body fat which in turn reduces overall body mass and improves metabolic parameters such as insulin resistance. These studies indicate that weight bearing exercise, in addition to endurance training, may benefit overweight people.
Researchers engineered a genetic “switch” in the mice that caused them to grow type II muscle fibers. The muscle mice, when compared with their regular cohorts, were stronger and faster but lacked the endurance of the regular mice. With the muscle building gene deactivated, the mice were then fed a high sugar and high fat diet. Not surprisingly, the mice became obese and developed insulin resistance. When the gene was reactivated and the same diet continued, the mice lost body fat and demonstrated better metabolic function as they gained muscle fiber. The researchers connected the ability of the mice to lose fat with “changes in the physiology and gene expression of their fat and liver cells.” They also noted the suggestion that type II muscle fiber “orchestrates changes in the body through its ability to communicate with…other tissues.”
The study underscores the importance of resistance training for overall health and particularly emphasizes strength in relation to the aging, which primarily depletes type II muscle fibers. Too many people assume that aging and disease go hand in hand. This study, in addition to many others, indicates once again that our choices can significantly influence our health in later years. Commentators for Cell Metabolism, the journal that published the study results, suggest that efforts to build muscle mass can serve as “critical weapons in the fight against obesity and obesity-related comorbidities including diabetes, heart disease, stroke, hypertension, and cancer.”
A quick curmudgeonly aside: don’t you wish summaries of these studies received as much air time as Big Pharma ads? We just need to add some light hearted music, fun graphics or picturesque settings, and a few attractive people. Any volunteers?
In all seriousness, consider the news a little extra motivation to hit the weight room this week. And be sure to check out what Mark and several of our readers suggested yesterday about the role of recovery in weight training.
Sponsor note: This post was brought to you by the Damage Control Master Formula, independently proven as the most comprehensive high-potency antioxidant multivitamin available anywhere. With the highest antioxidant per dollar value and a complete anti-aging, stress, and cognition profile, the Master Formula is truly the only multivitamin supplement you will ever need. Toss out the drawers full of dozens of different supplements with questionable potency and efficacy and experience the proven Damage Control difference!