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We investigated the effect of Eleutherococcus senticosus Maxim L (ESML) on performance during submaximal and maximal aerobic exercise. Twenty highly trained distance runners randomly assigned in matched pairs to either an experimental (ESML) or placebo (PL) group, participated in an 8-wk double-blind study during which they completed five trails of a 10-min treadmill run at their 10 km (10K) race pace and a maximal treadmill test (T(max)). Following a baseline trail, ESML and PL consumed, respectively, 3.4 ml of ESML extract or placebo daily for 6 wk. Subjects were tested every 2 wk during supplementation and 2 wk following withdrawal. Heart rate (HR), oxygen consumption (VO2), expired minute volume (VE), ventilatory equivalent for oxygen (VE/VO2), respiratory exchange ratio (RER), and rating of perceived exertion (RPE) were measured during the 10K and T(max) tests. Resting, post-10K and post-T(max) blood samples were analyzed for serum lactate. No significant differences were observed between ESML and PL for: HR, VO2, VE, VE/VO2, RER, or RPE; T(max) time to exhaustion; or serum lactate. The data do not support an ergogenic effect of ESML supplementation on selected metabolic, performance, or psychologic parameters associated with submaximal and maximal aerobic exercise tasks.

Creatine supplementation has been shown to augment muscle PCr content and increase the rate of ATP resynthesis. Thus, we hypothesized that creatine supplementation might enhance sprinting performance. Eighteen subjects completed both of two testingsessions(control and postsupplement) 1 week apart, wherein they sprinted three 60-m distancetrialsthat were recorded with videotape. Following the control session, for 7 days, subjects in the treatmentgroupingested a creatine-glucose mixture, while the placebogroupconsumed a glucose powder, followed by the postsupplementation session. Velocities of the subjects through three testingzoneswithin the 60-m sprint were calculated from the videotape. Resultant velocities were analyzed using a MANOVA with a2x2x3x3 (Group x Session x Trial x Zone) design. Results indicated that there were no statistically significant main or interaction effects on velocity between groups for session, trial, or zone. These data do not support the hypothesis that supplementary creatine ingestion will enhance velocity during the early or latter segments of a 60-m sprint.

Lumbosacral supports (LSSs) have been used to minimize the risk of lower back injuries. Theoretically, an LSS will raise intra-abdominal pressure (IAP) and reduce loads in the lower back region. This investigation compared three different LSSs with an unsupported condition. Nine males lifted a weighted box four times, once per condition, at 90% of their one-repetition maximum. Conditions were compared in terms of effects on IAP and its relieving force on L5-S1 kinetics. A multivariate analysis of covariance revealed no statistically significant differences among the three LSSs and the nonsupport conditions on the aforementioned dependent variables. This suggests that there is no difference among LSSs in terms of their biomechanical effects on the lower back region and that the use of any LSS does not necessarily afford more protection than a proper lift without one.

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