Effect of High-Intensity Interval Training Combined with L-Citrulline Supplementation on Functional Capacities and Muscle Function in Dynapenic-Obese Older Adults.
J Clin Med. 2018 Dec 17 ;7(12). Epub 2018 Dec 17. PMID: 30562948
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 (= 26; age: 6 5± four years) vs. HIIT+Placebo (PLA,= 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 (= 0.04) and upper limbs muscle strength (absolute and relative) (= 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.