Effect of diet‐induced weight loss on muscle strength in adults with overweight or obesity – a systematic review and meta‐analysis of clinical trials

Abstract

We conducted a systematic review and meta-analysis to identify how diet-induced weight loss in adults with overweight or obesity impacts on muscle strength. Twenty-seven publications, including 33 interventions, most of which were 8-24 weeks in duration, were included. Meta-analysis of seven interventions measuring knee extensor strength by isokinetic dynamometry in 108 participants found a significant decrease following diet-induced weight loss (-9.0 [95% confidence interval: -13.8, -4.1] N/m, P < 0.001), representing a 7.5% decrease from baseline values. Meta-analysis of handgrip strength from 10 interventions in 231 participants showed a non-significant decrease (-1.7 [-3.6, 0.1] kg, P = 0.070), with significant heterogeneity (I(2) = 83.9%, P < 0.001). This heterogeneity may have been due to diet type, because there was a significant decrease in handgrip strength in seven interventions in 169 participants involving moderate energy restriction (-2.4 [-4.8, -0.0] kg, P = 0.046), representing a 4.6% decrease from baseline values, but not in three interventions in 62 participants involving very-low-energy diet (-0.4 [-2.0, 1.2] kg, P = 0.610). Because of variability in methodology and muscles tested, no other data could be meta-analyzed, and qualitative assessment of the remaining interventions revealed mixed results. Despite varying methodologies, diets and small sample sizes, these findings suggest a potential adverse effect of diet-induced weight loss on muscle strength. While these findings should not act as a deterrent against weight loss, due to the known health benefits of losing excess weight, they call for strategies to combat strength loss - such as weight training and other exercises - during diet-induced weight loss. © 2016 World Obesity.

Effects of Weight Loss on Lean Mass, Strength, Bone, and Aerobic Capacity

“…The standard error of repeated isokinetic strength measures is ~6–13 Nm or 6–9% (18, 29), indicating good reliability; nonetheless, these tests may not have been sensitive enough to detect small reductions in strength that may have occurred as a consequence of the small 2 – 4% decrease in lower extremity lean mass. Based on a recent meta-analysis of 5 trials (n=98 participants), moderate calorie restriction with 6.2± kg weight loss reduces isokinetic knee extensor strength by 5.2% (p<0.0001) but does not alter isokinetic knee flexor strength or handgrip strength (38). The lack of change in BMD and BMC in the CR group was also unexpected, especially in light of significant reductions in dietary protein and calcium.…”

Vergleich von hoch- und mittelintensiven Gewichtsabnahmeprogrammen bei Adipositas Grad 2 und 3 – eine randomisierte klinische Untersuchung

“…Dabei ist zu beachten, dass die langfristigen Veränderungen des Gewichtsverlusts auf diese Parameter nur aufrechterhalten werden können, wenn die Patienten bereit sind, weiter konsequent zu trainieren und Diät zu halten [28]. Sinnvoll erscheint auch ein Krafttraining als Strategie zur Bekämpfung des Kraftverlusts während der diätetischen Gewichtsabnahme [33].…”

Diet and exercise interventions for pediatric cancer patients during therapy: tipping the scales for better outcomes

“…While diet modification can play a role in controlling obesity and BMI, there can be adverse effects of diet-induced weight loss on muscle strength (50). There can be a significant loss of fat-free mass depending on the diet modification and the calorie reduction.…”

“…There can be a significant loss of fat-free mass depending on the diet modification and the calorie reduction. Strategies such as weight training or aerobic exercise can combat the loss of muscle mass and strength (50). Physical activity (PA) can also play a role in controlling BMI and obesity as energy balance is defined as calories consumed – energy expended.…”