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The aim of this study was to examine the relationship between rectus femoris muscle architecture and isokinetic concentric peak knee extension torque at various velocities. Twenty physically active men (age =21.1±1.41 years, weight =69.9±5.7 kg, height =176.4±7.07 cm) had their isokinetic concentric knee extensor (Biodex 4 Pro, Biodex Medical Inc, Shirley, USA) strength assessed at 60°/sec, 180°/sec and 300°/sec. Pennation angle, muscle thickness, and fascicle length of the rectus femoris was measured using real-time B-mode ultrasound (Logiq P5, GE Healthcare, UK). Pennation angle had a significant positive correlation to peak torque at 60°/sec (r=0.731, p=0.001), 180°/sec (r=0.802, p=0.001) and 300°/sec (r=0.685, p=0.001). There was a significant positive correlation between muscle thickness and peak torque at 60°/sec (r=0.718, p=0.001), 180°/sec (r=0.749, p=0.001) and 300°/sec (r=0.722, p=0.001). However, there was no significant correlation between fascicle length and the isokinetic peak torque values (p>0.05). In addition, pennation angle and muscle thickness were found to be significant contributors for predicting isokinetic knee extension torque (R2=0.47-0.64; p<0.01). Pennation angle and muscle thickness best predicted peak knee extension torque at 180°/sec (explained variance =64% and 56%, respectively). This study suggests that pennation angle and muscle thickness can be used to predict isokinetic knee extension torque in physically active men. [ABSTRACT FROM AUTHOR]

Traditional continuous training and high-intensity interval training (HIIT) can increase maximal oxygen uptake (V̇O2max). However, there is conflicting evidence regarding which form of training demonstrates the greatest improvements to V̇O2max , and data in women is sparse. We conducted a systematic review and meta-analyses to assess whether moderate to vigorous-intensity continuous training (MVICT) or HIIT was superior at improving V̇O2max in women. Randomised controlled and parallel studies examined the influence of MVICT and/or HIIT on V̇O2max in women. There was no statistical difference in V̇O2max improvements after training between women in the MVICT and HIIT cohorts (mean difference [MD]: −0.42, 95%CI: −1.43 to 0.60, p>0.05). Both MVICT and HIIT increased V̇O2max from baseline (MD: 3.20, 95% CI: 2.73 to 3.67 and MD: 3.16, 95% CI 2.09 to 4.24, respectively, p<0.001). Greater improvements in V̇O2max were observed in women who participated in more training sessions in both training formats. Long-HIIT was superior to short-HIIT protocols at increasing V̇O2max. Although MVICT and long-HIIT sessions elicited greater increases in V̇O2max in younger women compared to short-HIIT protocols, these differences were negligible in older women. Our findings suggest MVICT and HIIT are equally effective strategies for improving V̇O2max and indicate an effect of age on its response to training in women. [ABSTRACT FROM AUTHOR]

Reliable measures of muscle strength and functional capacity in older adults are essential. The aim of this study was to determine whether coefficients of variation (CVs) of individuals obtained at the first session can infer repeatability of performance in a subsequent session. Forty-eight healthy older adults (mean age 68.6 ± 6.1 years; age range 60–80 years) completed two assessment sessions, and on each occasion undertook: dynamometry for isometric and isokinetic quadriceps strength, 6 meter fast walk (6MFWT), timed up and go (TUG), stair climb and descent, and vertical jump. Significant linear relationships were observed between CVs in session 1 and the percentage difference between sessions 1 and 2 for torque at 60, 120, 240 and 360°/s, 6MFWT, TUG, stair climb, and stair descent. The results of this study could be used to establish criteria for determining an acceptably reliable performance in strength and functional tests. [ABSTRACT FROM AUTHOR]

Objectives: Uncoupled cycling cranks are designed to remove the ability of one leg to assist the other during the cycling action. It has been suggested that training with this type of crank can increase mechanical efficiency. However, whether these improvements can confer performance enhancement in already well-trained cyclists has not been reported. Method: Fourteen well-trained cyclists (13 males, 1 female; 32.4 ± 8.8 y; 74.5 ± 10.3 kg; Vo2max 60.6 ± 5.5 mL·kg-1·min-1; mean ± SD) participated in this study. Participants were randomized to training on a stationary bicycle using either an uncoupled (n = 7) or traditional crank (n = 7) system. Training involved 1-h sessions, 3 days per week for 6 weeks, and at a heart rate equivalent to 70% of peak power output (PPO) substituted into the training schedule in place of other training. Vo2max, lactate threshold, gross efficiency, and cycling performance were measured before and following the training intervention. Pre- and posttesting was conducted using traditional cranks. Results: No differences were observed between the groups for changes in Vo2max, lactate threshold, gross efficiency, or average power maintained during a 30-minute time trial. Conclusion: Our results indicate that 6 weeks (18 sessions) of training using an uncoupled crank system does not result in changes in any physiological or performance measures in well-trained cyclists. [ABSTRACT FROM AUTHOR]

The article provides information on aspects related to utility of vibration exercise as warm-up modality in overground sprinting for Australian footballers. Topics discussed include measurement of individual comforts and normality assessment, measurements of analysis of variance, and sprinting measurements.