The Effect of Self-Paced and Prescribed Inter-Set Rest Strategies on Performance in Strength Training.

PURPOSE: To assess pacing strategies using prescribed and self-selected inter-set rest periods and their influence on performance in strength trained athletes. METHODS: Sixteen strength-trained male athletes completed three randomised heavy-strength training sessions (five sets, five repetitions) with different inter-set rest periods. The inter-set rest periods were: 3 minute (3MIN), 5 minute (5MIN) and Self-Selected (SS). Mechanical (power, velocity, work and displacement), surface muscle activity (sEMG) and subjective (Rating of Perceived Exertion -RPE) and readiness to lift (RTL) data were recorded for each set. RESULTS: SS condition inter-set rest periods increased from sets 1 to 4 (207.52s > 277.71 s; p=0.01). No differences in mechanical performance were shown between the different inter-set rest period conditions. Power output (210 W; 8.03%) and velocity (0.03 m.s-1; 6.73%) decreased as sets progressed for all conditions (p<0.001) from set 1 to set 5. No differences in sEMG activity between conditions were shown, however vastus medialis sEMG decreased as the sets progressed for each condition (1.75%; p=0.005). All conditions showed increases in RPE as sets progressed (set 1: 6.1; set 5: 7.9) (p<0.001). Participants reported greater readiness to lift in the 5MIN condition (7.81) compared to the 3MIN (7.09) and SS (7.20) conditions (p<0.001). CONCLUSIONS: Self-selecting inter-set rest periods does not significantly change performance compared to 3MIN and 5 MIN conditions.. Given the opportunity, athletes will vary their inter-set rest periods to complete multiple sets of heavy strength training. Self-selection of inter-set rest periods may be a feasible alternative to prescribed inter-set rest periods.

Probing the future of mandatory retirement in Canada.

The future of mandatory retirement is at least partly driven by changing demographics. In Canada, these demographics include slowing population growth, rapid aging, declining rates of labour force participation, and slowing labour force growth. After reviewing the demographic trends and considering alternate scenarios in labour force participation, we consider the determinants of early departures from the labour force and suggest scenarios that might reverse these trends. With a decline in labour force entrants, delays in early life transitions, and possible reductions in retirement benefits, a trend to retire later would bring mandatory retirement into question.