Effect of High-Intensity Interval Training Combined with L-Citrulline Supplementation on Functional Capacities and Muscle Function in Dynapenic-Obese Older Adults.

Fanny Buckinx,Vincent Marcangeli,Maude Dulac,Gilles Gouspillou,Guy El Hajj Boutros,Pierette Gaudreau,Mylène Aubertin-Leheudre,Philippe Noirez,José Morais,Livia Carvalho

doi:10.3390/jcm7120561

Abstract

Background: To compare the effects of high-intensity interval training (HIIT) alone vs. HIIT combined with L-citrulline (CIT) supplementation on functional capacity and muscle function in dynapenic-obese elderly. Methods: A total of 56 obese (fat mass: men > 25%, women > 35%) and dynapenic (grip strength/body weight: women < 0.44, men < 0.61) subjects were recruited and divided in two groups: HIIT+CIT (n = 26; age: 6 5 ± four years) vs. HIIT+Placebo (PLA, n = 30; age: 68 ± four years). Participants followed a 12-week HIIT using an elliptical trainer. Participants took a single and isocaloric 10 g-dose of CIT or PLA every day. Body composition; functional and aerobic capacities; absolute or relative upper and lower limbs muscle strength, muscle power; and energy balance were measured pre and post intervention. Results: Both groups significantly improved functional capacity and muscle function. However, HIIT+CIT demonstrated greater improvements in fast-paced Timed Up & Go (p = 0.04) and upper limbs muscle strength (absolute and relative) (p = 0.05) than HIIT+Placebo. Conclusion: CIT supplementation when combined with HIIT seems to induce greater improvements in upper limbs muscle strength and walking speed in dynapenic-obese elderly. Further studies are needed to confirm our results, to elucidate the mechanisms underlying the beneficial effects of CIT and to define the long-term impact of CIT/HIIT.

Highlights

Aging is often associated with a progressive loss of muscle strength and an increase in fat mass, both leading to physical declines [1]
Our results are consistent with recent meta-analyses in adults with obesity suggesting that high-intensity interval training (HIIT) is effective to improve VO2max and cardiometabolic risk factors [11,53]
The present study highlights that CIT supplementation combined with HIIT is feasible and effective to improve overall walking speed and upper muscle strength in dynapenic-obese older adults

Summary

Introduction

Aging is often associated with a progressive loss of muscle strength (dynapenia) and an increase in fat mass (obesity), both leading to physical declines [1]. Exercise interventions have been shown to improve multiple parameters related to dynapenia or obesity, including muscle function, fat mass, as well as functional and aerobic capacities. Despite this knowledge, almost 60% of older adults are sedentary [7]. To compare the effects of high-intensity interval training (HIIT) alone vs HIIT combined with L-citrulline (CIT) supplementation on functional capacity and muscle function in dynapenic-obese elderly. HIIT+CIT demonstrated greater improvements in fast-paced Timed Up & Go (p = 0.04) and upper limbs muscle strength (absolute and relative) (p = 0.05) than HIIT+Placebo. Conclusion: CIT supplementation when combined with HIIT seems to induce greater improvements in upper limbs muscle strength and walking speed in dynapenic-obese elderly. Further studies are needed to confirm our results, to elucidate the mechanisms underlying the beneficial effects of CIT and to define the long-term impact of CIT/HIIT

Methods

Findings

Discussion

Conclusion