Estimating physical working capacity and training changes in the elderly at the fatigue threshold (PWC_ft)

Abstract

The test for estimating physical working capacity at the fatigue threshold (PWCft), previously validated for young men, was evaluated for use with elderly men and women. A sample of 27 volunteer subjects (67.6 +/- 5.6 years, 11 male, 16 female) was divided into three matched groups: (1) controls (n = 10), (2) low intensity (70% PWCft) training group (n = 10) and (3) high intensity (85% PWCft) training group (n = 7). The subjects were tested for PWCft before and after 10 weeks of exercise training on cycle ergometers (30 min/day, 3 days/week). Controls did not exercise but met once a week for a health lecture. No significant pre-test to post-test change was noted in the mean PWCft of the control group (78.8-78.5 W); low intensity training resulted in 29.8% improvement in PWCft (81.0 to 105.0 W); and the high intensity group realized an improvement of 38.4% (83.6-115.7 W). One-way ANOVA indicated that the gains made by each of the groups were significantly different (p less than 0.01). Post hoc analysis revealed that the gains made by each exercise training group were significantly greater than controls (p less than 0.05) with no significant difference between high and low intensity groups. Reproducibility of the PWCft was excellent (R = 0.976). Since RPE averaged 14.2 at PWCft and 64% of subjects provided useful data, this test appears to be useful for evaluating the fitness of the elderly.

C‐terminal agrin fragment is inversely related to neuromuscular fatigue in older men

“…The primary finding is that serum CAF concentrations were related inversely ( r = −0.602) to the onset of neuromuscular fatigue via PWC FT independent of age and BMI in men only. Our previous work has shown PWC FT to be sensitive for detecting sarcopenia risk as identified by ALBM . The current results also support published data showing CAF to be related inversely to ALBM in men, but not women, which suggests that the etiology of muscle loss with aging in men may be associated strongly with degeneration of the neuromuscular junction as measured by CAF, whereas, in women, sarcopenia may be more multifaceted .…”

The effects of innervation zone on electromyographic amplitude and mean power frequency during incremental cycle ergometry

“…Surface EMG has also been used during cycle ergometry to develop tests for identifying the power output associated with the onset of fatigue for the superficial muscles of the quadriceps femoris (deVries et al, 1982(deVries et al, , 1987 Housh et al, 1996), examine the physiological mechanisms underlying neuromuscular fatigue (Housh et al, , 1991, quantify the effects of endurance training in the elderly (deVries et al, 1989), describe muscle activation patterns during submaximal Housh et al, 2000) and supramaximal (Hunter et al, 2003;Vandewalle et al, 1991) workbouts, and examine the relationship between the "iEMG threshold" and the "aerobic-anaerobic transition" in elite cyclists (Lucia et al, 1999) and cardiac transplant patients (Lucia et al, 1997). In addition, recent studies have examined the relationship between muscle activation patterns and the slow component of oxygen uptake kinetics during constant power output exercise for the moderate, heavy, and severe exercise domains (Jones and Poole, 2004;Lucia et al, 2000;Scheuermann et al, 2001;Shinohara and Moritani, 1992).…”

The effects of interelectrode distance on electromyographic amplitude and mean power frequency during incremental cycle ergometry

“…doi:10. 1016/j.jneumeth.2005.06.025 the onset of fatigue for the superficial muscles of the quadriceps femoris (deVries et al, 1982(deVries et al, , 1987Evetovich et al, 1996;Housh et al, 1996), examine the physiological mechanisms underlying neuromuscular fatigue (Housh et al, , 1991, quantify the effects of endurance training in the elderly (deVries et al, 1989), describe muscle activation patterns during submaximal Housh et al, 2000) and supramaximal (Hunter et al, 2003;Vandewalle et al, 1991) workbouts, and examine the relationship between the "iEMG threshold" and the "aerobic-anaerobic transition" in elite cyclists (Lucia et al, 1999) and cardiac transplant patients (Lucia et al, 1997). In addition, recent studies have examined the relationship between muscle activation patterns and the slow component of oxygen uptake kinetics during constant power output exercise for the moderate, heavy, and severe exercise domains (Jones and Poole, 2004;Lucia et al, 2000;Scheuermann et al, 2001;Shinohara and Moritani, 1992).…”