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Purpose: Maximum force exertion against various resistance levels (heavy-light) is commonly implemented to improve both strength- and speed-oriented components of power. Medium-light resistances allow rapid accelerations, yet incur significant decelerations in the later concentric phase to bring the bar to a halt, which may limit the concentric effort and, therefore, the effectiveness of training. Accordingly, ballistic actions have been recommended. This study evaluated the effectiveness of power bench press training, with the bar thrown on a Smith machine (BPthrow) or without throwing (BPnon-throw), for developing strength and shot put distance.Methods: Nine university shot-putters performed BPthrow and BPnon-throw at 50, 40 and 30% 1RM, as well as seated and standing shot put trials. Peak angular velocities at the elbow were measured in these tasks using a wireless electro-goniometer. Participants underwent 24 sessions of training (12 weeks) with either BPthrow (n = 5) or BPnon-throw (n = 4) at the three intensities (20 s × 2 sets at 50, 40 and 30% 1RM).Results: The peak elbow velocity during BPthrow was 1.7 times greater than BPnon-throw for all intensities. The velocity of BPthrow at 30% 1RM (854.7°/s), however, was still slower than seated (1121.3°/s) and standing (1539.1°/s) shot puts. BPthrow training significantly improved 1RM (+ 10.0%) and the distances of seated (+ 11.7%) and standing (+ 3.8%) shot puts, while no performance changes occurred after BPnon-throw training.Conclusion: When undergoing power bench press against medium-light resistances, maximum ballistic actions are important strategies for improving 1RM and shot put performance of university shot-putters. [ABSTRACT FROM AUTHOR]

Purpose: To identify whether variability in limb movement velocity during high-speed power training (HSPT) may impact physical functioning in older adults. Methods: 42 older men and women (71.3 ± 6.6 years) were randomized to lower extremity HSPT ( n = 28) or control (CON; n = 14) (Analysis 1) for 12 weeks. A second analysis (Analysis 2) allocated HSPT into high-velocity ( n = 14) or low-velocity ( n = 14) based on a limb movement speed above or below the median average velocity during the 12-week HSPT intervention. Habitual gait speed, maximal gait speed, timed up-and-go, and the short physical performance battery were measured at baseline and 12 weeks. Change scores were compared between HSPT and CON (Analysis 1), and high-velocity, low-velocity, and CON (Analysis 2) using ANCOVA. Statistical significance was accepted at p < 0.05. Results: Analysis 1 There were no group differences in habitual gait speed, maximal gait speed, or timed up-and-go between HSPT and CON (all p > 0.05). Short physical performance battery was greater in HSPT (0.96 ± 0.19) compared to CON (0.10 ± 0.26; p = 0.01). Analysis 2 There were no group differences in the change in habitual GS ( p = 0.33) among high-velocity, low-velocity and CON. There were significant group differences in the change in maximal GS ( p = 0.007), timed up-and-go ( p = 0.03), and short physical performance battery ( p = 0.03). Conclusions: There is considerable variation in self-selected maximal limb velocity during HSPT in older adults. In the present cohort, an average limb velocity of 0.88 m/s during HSPT was necessary to ensure optimal improvement in functional performance for older adults, but this threshold will need further investigation. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to investigate the effects of low-intensity running performed immediately after lower-body power-training sessions on power development.Methods: Twenty young females participated in 6 weeks, 3/week, of either lower body power training (PT) or lower body power training followed by 30 min of low-intensity running (PET) eliciting 60-70 % of maximal heart rate. The following were measured before and after the training period: counter-movement jump, isometric leg press force and rate of force development (RFD), half squat 1-RM, vastus lateralis fiber type composition and cross sectional area, resting intramuscular fiber conduction velocity (MFCV), and heart rate during the modified Bruce treadmill test.Results: Counter-movement jump height and peak power increased after PT (10.7 ± 6.2 and 12.9 ± 18.7 %, p < 0.05) but not after PET (3.4 ± 7.6 and 5.11 ± 10.94 %, p > 0.05). Maximum isometric force, RFD, and half squat 1-RM increased similarly in both groups. Muscle fiber type composition was not altered in either group. Muscle fiber cross sectional area increased only after PT (17.5 ± 17.4, 14.5 ± 10.4, 20.36 ± 11.3 %, in type I, IIA, and IIX fibers, respectively, p < 0.05). Likewise, mean MFCV increased with PT only (before: 4.53 ± 0.38 m s(-1), after: 5.09 ± 0.39 m s(-1), p = 0.027). Submaximal heart rate during the Bruce treadmill test remained unchanged after PT but decreased after PET.Conclusion: These results suggest that low-intensity running performed after lower-body power training impairs the exercise-induced adaptation in stretch-shortening cycle jumping performance (vertical jump height, peak power), during the first 6 weeks of training, which may be partially linked to inhibited muscle fiber hypertrophy and muscle fiber conduction velocity. [ABSTRACT FROM AUTHOR]

This study investigated the effect of a 10-week power training (PT) program versus traditional resistance training (TRT) on functional performance, and muscular power and strength in older men. Twenty inactive volunteers (60-76 years old) were randomly assigned to a PT group (three 8-10 repetition sets performed as fast a possible at 60% of 1-RM) or a TRT group (three 8-10 repetition sets with 2-3 s contractions at 60% of 1-RM). Both groups exercised 2 days/week with the same work output. Outcomes were measured with the Rikli and Jones functional fitness test and a bench and leg press test of maximal power and strength (1-RM). Significant differences between and within groups were analyzed using a two-way analysis of variance (ANOVA). At 10 weeks there was a significantly (P < 0.05) greater improvement in measures of functional performance in the PT group. Arm curling improved by 50 versus 3% and a 30 s chair-stand improved by 43 versus 6% in the PT and TRT groups, respectively. There was also a significantly greater improvement in muscular power (P < 0.05) in the PT group. The bench press improved by 37 versus 13%, and the leg press by 31 and 8% in the PT and TRT groups, respectively. There was no significant difference between groups in improved muscular strength. It appears that in older men there may be a significantly greater improvement in functional performance and muscular power with PT versus low velocity resistance training. [ABSTRACT FROM AUTHOR]