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Purpose: We investigated the effect of ischemic preconditioning (IPC) on performance of a 3 min maximal effort arm ergometer test in young women.Methods: Twenty healthy women (23.1 (SD 3.3) years) performed a 3 min maximal effort arm cycling exercise, preceded by IPC on both arms or SHAM in a counterbalanced randomized crossover design. Both blood flow (via high resolution ultrasound; n = 17) and muscle oxygenation/deoxygenation (via near infrared spectroscopy; n = 5) were measured throughout the IPC/SHAM. Performance and perceptual/physiological (i.e., heart rate, blood lactate, rating of perceived exertion, and triceps brachialis oxygenation) parameters were recorded during the exercise test.Results: Occlusion during IPC completely blocked brachial artery blood flow, decreased oxygenated hemoglobin/myoglobin (Δ[oxy(Hb + Mb)]), and increased deoxygenated Hb/Mb (Δ[deoxy(Hb + Mb)]). There were no differences (P > 0.797) in performance (peak, mean, and end power output) or in any perceptual/physiological variables during the 3 min all-out test between IPC/SHAM. During exercise, Δ[oxy(Hb + Mb)] initially decreased with no differences (P ≥ 0.296) between conditions and returned towards baseline by the completion of the test while Δ[deoxy(Hb + Mb)] increased with no differences between conditions and remained elevated until completion of the test (P ≥ 0.755).Conclusions: We verified the successful application of IPC via blood flow and NIRS measures but found no effects on performance of a 3 min maximal effort arm cranking test in young women. [ABSTRACT FROM AUTHOR]

Purpose: Stroke rate (SR) has not been considered in previous research examining the relative roles of the limbs in front-crawl performance. This study compared velocity, aerobic power ([Formula: see text]) and metabolic cost (C) between whole body (WB) and arms only (AO) front-crawl swimming across various intensities while controlling SR.Methods: Twenty Australian national swimmers performed six 200 m front-crawl efforts under two conditions: (1) WB swimming and, (2) AO swimming. Participants completed the 200 m trials under three SR conditions: "low" (22-26 stroke-cycles min(-1)), "moderate" (30-34 stroke-cycles min(-1) and "high" (38-42 stroke-cycles min(-1)). [Formula: see text] was continuously measured, with C, velocity, SR, and kick rate calculated for each effort.Results: Regardless of the SR condition and sex, AO velocity was consistently lower than WB velocity by ~11.0 % (p < 0.01). AO [Formula: see text] was lower than WB [Formula: see text] at all SR conditions for females (p < 0.01) and at the "high" SR for males (p < 0.01). C did not differ between WB and AO at any SR for both sexes (p > 0.01). When C was expressed as a function of velocity, WB and AO regression equations differed for males (p = 0.01) but not for females (p = 0.087). Kick rate increased as SR increased (p < 0.01), though the kick-to-stroke rate ratio remained constant.Conclusion: Elite swimmers gain ~11 % in velocity from their kick and, when used in conjunction with the arm stroke at the swimmers' preferred frequency, the metabolic cost of WB and AO swimming is the same. Coaches should consider these results when prescribing AO sets if their intention is to reduce the metabolic load. [ABSTRACT FROM AUTHOR]

Resistance training is widely recommended to prevent sarcopenia and osteoporosis. However, the effects of upper and lower limb resistance training on arterial stiffness are unclear. The present study investigates the effects of upper and lower limbs resistance training on arterial stiffness. Thirty young healthy subjects (male 19, female 11, aged 20.1 +/- 0.4 years, mean +/- SD) were randomly assigned to upper limb RT group (upper limb group, n = 10, male 7, female 3), lower limb RT group (lower limb group, n = 10, male 7, female 3) and sedentary groups (n = 10, male 6, female 4). The upper and lower limb groups performed RT at 80% of one repetition maximum twice each week for 10 weeks. Arterial stiffness was measured by brachial-ankle pulse wave velocity (baPWV). In addition, we measured plasma norepinephrine (NE) concentration. baPWV after training in the upper limb group had significantly increased from baseline (P < 0.05). In addition, plasma NE concentration after training in the upper limb group had significantly increased from baseline (P < 0.05). No such changes were observed in the lower limb and sedentary groups. Moreover, a significant positive correlation between baPWV and plasma NE concentration in upper limb group was observed (P < 0.05). In contrast, no significant correlation between baPWV and plasma NE concentration in lower limb and sedentary groups was observed. These findings suggested that upper limbs resistance training increases plasma NE concentration and promotes the increase of arterial stiffness. [ABSTRACT FROM AUTHOR]