Aerobic and Resistance Exercise Preserve Muscle in Older People with Obesity

Key Takeaway

• Combining aerobic exercise and resistance training helps older obese individuals preserve muscle mass and reverse frailty as they lose weight

Published in Cell Metabolism, this study showed that patients who completed the exercises had increased muscle protein synthesis and preserved muscle quality compared to control groups.

Background

In a previous study, Dennis T. Villareal, professor and geriatric endocrinologist at Baylor College of Medicine, hypothesized that resistance training would best complement weight loss for improving physical function in older obese adults.

Study participants took part in a weight-management program and were randomly assigned aerobic workouts, resistance training or a combination of both.

Researchers were surprised to find that combined aerobic and resistance training:

Improved cardiovascular fitness to the same extent as aerobic training alone

Improved muscle strength to the same extent as resistance training alone

However, it was unclear how obese older adults in particular benefitted from aerobic workouts geared toward cardiovascular fitness combined with resistance training.

The New Study

Researchers used molecular and cellular techniques to assess changes underlying the obese older adults' improvement in physical function and preservation of lean body mass.

A subset of participants (men and women aged 69-72), agreed to undergo muscle biopsies before and after six months of lifestyle interventions to see how their muscle tissue was affected.

Participants exercised at approximately 65% of their peak heart rate during aerobic activities which included:

• Treadmill walking
• Stationary cycling
• Stair climbing

Resistance training consisted of 1-3 sets of 8-12 reps on nine upper-body and lower-body weight-lifting machines.

The Results

"Our findings indicated that despite negative energy balance from diet-induced weight loss, exercise training in older adults with obesity helps to preserve muscle mass, improve physical function and reduce frailty," Villareal says.

In the elderly obese, combined aerobic and resistance exercise is superior to either mode independently for maintaining muscle mass during weight-loss therapy, he says. Aerobic and resistance training is the most effective strategy and therefore, Villareal notes, "the best approach."

References

Aerobic Plus Resistance Exercise in Obese Older Adults Improves Muscle Protein Synthesis and Preserves Myocellular Quality Despite Weight Loss Cell Metabolism

Aerobic or Resistance Exercise, or Both, in Dieting Obese Older Adults The New England Journal of Medicine