This study was conducted to test the hypothesis that a branched-chain amino acid (BCAA) supplementation would minimize changes in body composition and alterations in plasma amino acid profile induced by prolonged exercises at altitude. Twenty-four highly trained subjects participated in six successive sessions of ski mountaineering (6-8 hr duration, altitude 2,500-4,100 m). Twelve subjects took a dietary supplement of BCAA (BCAA group) and 12 took a dietary supplement that was 98% carbohydrate (C group). Body weight decreased in C subjects (-2.1%,p < .01), while the body weight loss recorded in the BCAA group was not statistically significant (-1.2%, NS). Changes in body composition that resulted from repeated skiing exercise at altitude were not significantly minimized by BCAA administration. Peak power output recorded during an incremental bicycle exercise decreased in C subjects but did not change significantly in BCAA subjects. Results of this study demonstrate that neither changes in body composition related to the ski mountaineering program nor muscular performance during isometric contraction was significantly affected by BCAA administration.

The nerve fibres of largest diameter and of greatest length are considered to be the most vulnerable to triorthocresyl phosphate (TOCP). In this study, the differential vulnerability of the particular sciatic nerve branches was determined in the course of TOCP neuropathy and of Wallerian degeneration. The branch innervating the lateral gastrocnemius muscle, made up predominantly of large-diameter fibres, proved most susceptible to TOCP. By contrast, after proximal sciatic-nerve transection, degeneration commenced in the lateral nerve of the third digit, containing long nerve fibres of small diameter.

The APS Journal Legacy Content is the corpus of 100 years of historical scientific research from the American Physiological Society research journals. This package goes back to the first issue of each of the APS journals including the American Journal of Physiology, first published in 1898. The full text scanned images of the printed pages are easily searchable. Downloads quickly in PDF format.

During the seasonal aerial application of insecticides on cotton, a cholinesterase surveillance program was realized and the adherence of the safety measures in connection with insecticides was supervised. No cases of ill health or poisoning due to the handling of the insecticides are known to have occurred amongst the pilots, entomologists, and aircraft engineers. Only a small number of ground personnel and landing strip workmen showed temporarily depressed cholinesterase levels while engaged in this program.

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