Different response to eccentric and concentric training in older men and women

Abstract

Sarcopenia is the age-related loss of muscle mass and strength and has been associated with an increased risk of falling and the development of metabolic diseases. Various training protocols, nutritional and hormonal interventions have been proposed to prevent sarcopenia. This study explores the potential of continuous eccentric exercise to retard age-related loss of muscle mass and function. Elderly men and women (80.6 +/- 3.5 years) were randomized to one of three training interventions demanding a training effort of two sessions weekly for 12 weeks: cognitive training (CT; n = 16), conventional resistance training (RET; n = 23) and eccentric ergometer training (EET; n = 23). Subjects were tested for functional parameters and body composition. Biopsies were collected from M. vastus lateralis before and after the intervention for the assessment of fiber size and composition. Maximal isometric leg extension strength (MEL: +8.4 +/- 1.7%) and eccentric muscle coordination (COORD: -43 +/- 4%) were significantly improved with EET but not with RET (MEL: +2.3 +/- 2.0%; COORD: -13 +/- 3%) and CT (MEL: -2.3 +/- 2.5%; COORD: -12 +/- 5%), respectively. We observed a loss of body fat (-5.0 +/- 1.1%) and thigh fat (-6.9 +/- 1.5%) in EET subjects only. Relative thigh lean mass increased with EET (+2.5 +/- 0.6%) and RET (+2.0 +/- 0.3%) and correlated negatively with type IIX/type II muscle fiber ratios. It was concluded that both RET and EET are beneficial for the elderly with regard to muscle functional and structural improvements but differ in their spectrum of effects. A training frequency of only two sessions per week seems to be the lower limit for a training stimulus to reveal measurable benefits.

Eccentric Resistance Training in Adults with and without Spinal Cord Injuries

“…However, the participants with iSCI in the current sample demonstrated a greater ability to apply strength from ERT to isometric actions than older adults in a prior investigation, improving 41.5% post ERT versus 7.5%, respectively (22). Participants in the CON group improved isometric strength more similarly to the older adults with gains of 8.5-9.5%, when excluding the participant with osteoarthritis (22). Inconsistency in isometric force improvement between individuals in the CON and iSCI groups may be attributed to a greater capacity for neural improvement because of the lower baseline neural capabilities for those with iSCI.…”

“…While the effects of eccentric training have not been established specifically in persons with iSCI, it has been shown to increase muscle size in those following anterior cruciate ligament repair, younger, and older adults (10,17,25), strength in younger and older adults with and without heart disease (9,17,20,22,25), and aerobic capacity in young and older adults with heart disease (11,18). Further, the lower metabolic cost of ERT may allow individuals with iSCI to perform more work during an exercise session compared to concentrically-based programs (18).…”

Ultrastructure of pedal muscle as a function of temperature in nacellid limpets

“…Limpet myocytes are 1-2 orders of magnitude smaller than vertebrate skeletal myocytes (Hoppeler et al 1973;Johnston et al 1998;Mueller et al 2009), but similar in size to brachiopod myocytes (Liothyrella spp. ; Lurman et al 2010).…”

Metabolic Exploration of Muscle Biopsy

“…Biopsies of vastus lateralis demonstrated an increased volume of myofibrils, an increased proportion of type IIa muscle fibres and an www.intechopen.com enhanced transcription of IGF-1 in the eccentric group (Zoll et al, 2006b). For the elderly patients (mean age = 80 yr old), eccentric cycle ergometry induced a greater gain in isometric strength of the knee extensors (Mueller et al, 2009), as compared with a conventional resistance training program. In this study, biopsies of vastus lateralis showed an enhanced expression of transcripts encoding factors involved in muscle growth, repair and remodeling (i.e.…”