Volleyball has been described as an 'interval' sport with both anaerobic and aerobic components. At the higher skill levels, technical performance may be limited by physical characteristics as well as physical fitness, and performance characteristics such as speed and vertical jump. This investigation compared teams at the two uppermost levels of men's volleyball in Canada for differences in physical, physiological and performance characteristics. The subjects were members of the national (n = 15) and universiade teams (n = 24). The parameters examined included percent body fat, maximal oxygen uptake (VO2 max), anaerobic power, bench press, 20-m sprint time and vertical jumping ability. The only significant difference in physical characteristics between the two teams was in age. Despite similarities in standing and reach height, the national team players had significantly higher block (3.27 vs 3.21 m) and spike (3.43 vs 3.39 m) jumps. An evaluation of anaerobic power measures produced similar power outputs during a modified Wingate test, yet the national team members had higher scores (P less than 0.05) for spike and block jump differences as well as 20-m sprint time. The large aerobic component of elite volleyball play was supported by the high VO2 max value recorded for the national team players (56.7 vs 50.3 ml kg-1 min-1). The results suggest that either years of specific physical conditioning and playing or the selection of individuals for the national team who possess more desirable characteristics as a consequence of genetic endowment, plays a significant role in the preparation of international calibre volleyball players.

The use of the pH-pill has allowed continuous monitoring of vaginal pH during human coitus. In the case of a couple of normal fertility, there was an immediate buffering by seminal plasma so that the vaginal pH changed in 8 sec from pH 4\m=.\3to pH 7\m=.\2.In the case of a couple of low (male) fertility, the immediate effect of the arrival of semen in the vagina was a change from pH 3\m=.\5to pH 5\m=.\5.A similarly small change in pH occurred when the seminal volume of a fertile male subject had been depleted, by repeated ejaculation, to 1 \ m=. \ 5ml. At this pH (5\m=.\5),spermatozoa are generally immobilized.It has been possible to alter normal fertility, as judged by postcoital tests for sperm motility, by the introduction of a pH 3\m=.\6buffer solution into the vagina before coitus. In this latter experiment, the vaginal pH immediately after ejaculation was 5\m=.\0 and, after 2 hr, had reached pH 5\m=.\4.These results in vivo suggest that the vagina is not the hostile environment hitherto imagined, since the normal ejaculate readily overcomes the vaginal acidity by its powerful buffering action. Low seminal volume, with or without a concomitantly low sperm count, and artificial changes in vaginal environment by buffer solutions may affect fertility.

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EDITORIAL SYNOPSIS The radio-telemetering capsule (radio-pill) has been used to study the return of motility in the small bowel after vagotomy with a drainage procedure, gastric operations not involving vagotomy, and non-gastric operations.Small intestinal movements returned in about 10 hours after vagotomy, about four hours after the various gastric operations, and within one hour in those operations not involving handling of the viscera.The implications of these results are discussed in relation to the management of patients after gastric surgery.

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