How To Lose Less Muscle With Weight Loss

One of the major challenges when losing weight is to not disproportionally lose muscle mass.

This happens all too easily not just because of “off-loading” but also when dietary intake fails to meet protein needs.

Now, a randomised controlled trial by Yoshimura and colleagues from Fukuoka University, Japan, published in Obesity Facts, shows that a healthy dose of aerobic exercise can decrease (but not fully prevent) muscle loss with energy restriction.

The researchers randomised 75 males and females to the groups ‘diet only’ or ‘diet plus aerobic exercise’ for 12 weeks.

In addition to maintaining a diet containing 25 kcal/kg of ideal body weight, subjects in the exercise group were instructed to exercise for ≥300 min/week at lactate threshold.

Both groups lost about 7% of body weight as well as about 20% visceral fat.

However, while the diet only group lost about 5% of their thigh muscle cross sectional area, this loss was reduced to half (2.5%) in the exercise group.

Thus, it appears that about 40 mins of daily aerobic exercise can attenuate (but not fully prevent) the loss of skeletal muscle during energy restriction in adults.

This alone, is a good reason to always encourage exercise prescriptions with weight loss.

@DrSharma
Edmonton, AB

Yoshimura E, Kumahara H, Tobina T, Matsuda T, Watabe K, Matono S, Ayabe M, Kiyonaga A, Anzai K, Higaki Y, & Tanaka H (2014). Aerobic Exercise Attenuates the Loss of Skeletal Muscle during Energy Restriction in Adults with Visceral Adiposity. Obesity facts, 7 (1), 26-35 PMID: 24457527