Acute Physiological Response to Light- and Heavy-load Power-oriented Exercise in Older Adults

Abstract

This study investigated the acute responses to volume-load-matched heavy-load (80% 1RM) versus light-load (40% 1RM) power-oriented resistance training sessions in well-functioning older adults. Using a randomized cross-over design, 15 volunteers completed each condition on a leg press. Neuromuscular (maximal isometric force and rate of force development) and functional performance (power during sit-to-stand test), lactate, and muscle damage biochemistry (creatine kinase, lactate dehydrogenase and C-reactive protein serum concentration) were assessed pre- and post-exercise. Performance declines were found after heavy-load (Cohen’s d effect size (d); maximal isometric force=0.95 d; rate of force development=1.17 d; sit-to-stand power =0.38 d, all p<0.05) and light-load (maximal isometric force=0.45 d; rate of force development=0.9 d; sit-to-stand power=1.17 d, all p<0.05), while lactate concentration increased only after light-load (1.7 d, p=0.001). However, no differences were found between conditions (all p>0.05). Both conditions increased creatine kinase the day after exercise (marginal effect=0.75 d, p<0.001), but no other blood markers increased (all, p>0.05). Irrespective of the load used, power training induced non-clinically significant decreases in sit-to-stand performance, moderate declines in maximal isometric force, but pronounced decreases in the rate of force development. Furthermore, the metabolic stress and muscle damage were minor; both sessions were generally well tolerated by well-functioning older adults without previous experience in resistance training.

Effectiveness of individualized training based on force–velocity profiling on physical function in older men

“…44 Additionally, other recent studies investigating adaptations to low-load power training in older participants have also been published. 45,46 The results from the GPT group are consistent with previous studies showing that a combination of heavy and low loads induces superior increases in power across the entire FV curve compared to training with either heavy or low loads alone. 39,40 Thus, it is speculated that power training with a combination of load ranges can affect both force-and velocity-related adaptations, resulting in greater total adaptation in power compared to training programs aiming at specifically force-or velocity-related adaptations.…”

“…Interestingly, a recent study in older subjects has, however, observed load‐specific adaptations in V 0 following low‐load power training 44 . Additionally, other recent studies investigating adaptations to low‐load power training in older participants have also been published 45,46 . The results from the GPT group are consistent with previous studies showing that a combination of heavy and low loads induces superior increases in power across the entire FV curve compared to training with either heavy or low loads alone 39,40 .…”

Effect of Resistance Training Programs With Equated Power on Older Adults' Functionality and Strength: A Randomized Controlled Trial

“…In this sense, a recent study (2) suggested that impaired muscle power might have its origin in deficits in both force and velocity, being both deficits associated with a lower physical function, quality of life, and higher frailty, whereas only force deficit was associated with a lower cognitive function. A more recent study by the same group (38) found that heavy-load power training improved the capability to generate large forces, whereas low-load power training enhanced movement velocity in older adults. Nevertheless, both interventions promoted similar increases in muscle power and muscle hypertrophy (38).…”

“…The study of the cardiovascular and neuromuscular adaptations produced by power training programs conducted under different loading conditions has received increasing attention (5,14,16). However, these and other studies used markedly different loads related to not equated levels of power (11,14,38,40); thus, the effects of load and velocity on the strength performance and functionality of older adults remain unclear. To the best of our knowledge, this is the first study on older people comparing the effects of 2 PRT equated by the power level close to the PP but differing in load and, consequently, in velocity.…”

“…A novelty of our study is that we contrasted the effects on strength and functionality of adding PRT in a sample of physically active older adults in comparison with the evolution of control older adults who also performed a regular traditional nonsupervised multicomponent training but not PRT. Previous studies have explored the effects of PRT interventions without control groups (14,38,40) or by contrast with control groups that did not exercise (11,27,32). In this regard, the lack of a group that maintains their physical exercise routines may hinder the assessment of the actual effect of the addition of a PRT on the functional capacity of active older adults.…”