Biologically relevant sex differences for fitness-related parameters in active octogenarians

Abstract

The number of elderly people is growing in western populations, but only few maximal performance data exist for people >75 years, in particular for European octogenarians. This study was performed to characterize maximal performance of 55 independently living subjects (32 women, 81.1 +/- 3.4 years; 23 men, 81.7 +/- 2.9 years) with a focus on sex differences. Maximal performance was determined in a ramp test to exhaustion on a bicycle ergometer with ergospirometry, electrocardiogram and blood lactate measurements. Maximal isometric extension strength of the legs (MEL) was measured on a force platform in a seated position. Body composition was quantified by X-ray absorptiometry. In >25% of the subjects, serious cardiac abnormalities were detected during the ramp test with men more frequently being affected than women. Maximal oxygen consumption and power output were 18.2 +/- 3.2 versus 25.9 +/- 5.9 ml min(-1) kg(-1) and 66 +/- 12 versus 138 +/- 40 W for women versus men, with a significant sex difference for both parameters. Men outperformed women for MEL with 19.0 +/- 3.8 versus 13.6 +/- 3.3 N kg(-1). Concomitantly, we found a higher proportion of whole body fat in women (32.1 +/- 6.2%) compared to men (20.5 +/- 4.4%). Our study extends previously available maximal performance data for endurance and strength to independently living European octogenarians. As all sex-related differences were still apparent after normalization to lean body mass, it is concluded that it is essential to differentiate between female and male subjects when considering maximal performance parameters in the oldest segment of our population.

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

“…Based on the study of LaStayo et al (Lastayo et al 2002), we hypothesized that EET would be more eVective in increasing muscle strength and mass than conventional resistance training. We further expected larger improvements of muscle strength in females than in males due to their initial lower Wtness level (Lotscher et al 2007). We did not expect any changes in muscle Wber type composition as the imposed training regime (2 £ 20 min eVective training time per week for 12 weeks) seemed to be insuYcient to produce Wber type changes.…”

“…During the Wrst sessions the training duration was gradually increased in 5-min steps until it reached 20 min, before the imposed load was ramped. Load was ramped in consecutive sessions by 20% of the individual maximal power output achieved in the initial ergometer ramp test to exhaustion (Lotscher et al 2007). Contraindications to increase the workload were the same as those for RET (DOMS; RPE).…”

“…Subjects with severe neuromuscular disease, instable coronary disease or severe hip or knee arthritis were excluded (Lotscher et al 2007). The study was part of the National Foundation Program 53 ''Musculoskeletal health and chronic pain'' and carried out in accordance with the guidelines and the approval #190/04 of the "Kantonale Ethische Kommission".…”

“…As the energy cost of eccentric work is approximately four times less than that of concentric work of a comparable external load (Lastayo et al 1999) large torques can be exerted at a manageable metabolic cost. The ensuing low stress on the cardiovascular system is particularly important for elderly, since they are characterized by a reduced aerobic capacity (Lotscher et al 2007). The objective of using EET thus was to achieve a high mechanical load on muscle tissue with a restricted aerobic demand.…”

Different Molecular and Structural Adaptations with Eccentric and Conventional Strength Training in Elderly Men and Women

“…In the following sessions, the duration was gradually increased in 5-min steps until it reached 20 min. Thereafter, the load was ramped in consecutive sessions by 20% of the individual maximal power output achieved in the initial incremental exercise test to exhaustion on a (concentric) cycling ergometer [15,21] . All groups trained for 12 weeks with two sessions per week.…”