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Biomedical subjects

W C Adams

Publications and source records attributed to W C Adams.

At least 73 records · Page 4Linked to original sources
PubMed1975

Effects of equivalent sea-level and altitude training on VO2max and running performance.

Twelve middle-distance runners, each having recently completed a competitive track season, were divided into two groups matched for maximal oxygen uptake (VO2max), 2-mile run time and age. Group 1 trained for 3 wk at Davis, PB = 760 mmHg, running 19.3 km/day at 75% of sea-level (SL) VO2max, while group 2 trained an equivalent distance at the same relative intensity at the US Air Force Academy (AFA), PB = 586 mmHg. The groups then exchanged sites and followed a training program of similar intensity to the group preceding it for an additional 3 wk. Periodic near exhaustive VO2max treadmill tests and 2-mile competitive time trials were completed. Initial 2-mile times at the AFA were 7.2% slower than SL control. Both groups demonstrated improved performance in the second trial at the AFA (chi = 2.0%), but mean postaltitude performance was unchanged from SL control. VO2max at the AFA was reduced initially 17.4% from SL control, but increased 2.6% after 20 days. However, postaltitude VO2max was 2.8% below SL control. It is concluded that there is no potentiating effect of hard endurance training at 2,300-m over equivalently severe SL training on SL VO2max or 2-mile performance time in already well conditioned middle-distance runners.

Adolescent↗
PubMedDate not supplied

Ozone dose-response effects of varied equivalent minute ventilation rates.

While it is well known that exercise minute ventilation (V(E)) results in greater pulmonary function and subjective symptoms (SS) responses upon exposure to a given ozone (O3) dose, the magnitude of V(E) increase to produce a significant forced expiratory volume in 1 s (FEV1.0) response compared to that observed at a lower exercise V(E) for the same O3 concentration and exposure time is unclear, especially in prolonged (i.e., >2 h) exposures. Further, in prolonged exposures, the relationship of body size to FEV1.0 response to a given O3 exposure dose has not been systematically examined. In the present study, 30 young adults were exposed on four occasions for 6 h (during a 6.6-h period) to constant 03 levels of zero (filtered air, FA) or 0.12 parts per million (ppm). At the latter concentration, exercise V(E) was varied in exposures to 17, 20, and 23 l min(-1) m(-2) of BSA, respectively, for each individual to achieve an equivalent ventilation rate, EVR). In the FA exposure, EVR was 23 l min(-1) m2. Percent changes in FEV1.0 for the three 0.12 ppm O3 exposures were significantly greater than that for FA, but did not differ significantly from each other. For the 6.6-h exposures, exercise EVR at or in excess of 17 l min(-1) m(-2), SS values were significantly greater than those observed for the FA protocol. Further, SS values at 6.6 h of exposure to 0.12 ppm O3 for the exercise EVR of 23 l min(-1) m(-2) protocol were significantly greater than for the 0.12 ppm O3 exercise EVR of 17 l min(-1) m(-2) protocol. To achieve a widened EVR, two 1-h exposures to 0.30 ppm O3 with continuous exercise (CE) at a level necessitating an EVR of 17 and approximately 34 l min(-1) m(-2), respectively, were completed by each subject. All postexposure pulmonary function and SS responses were significantly greater for the higher 1-h EVR protocol. In all exposures with significant O3-induced changes in FEV1.0 and SS, it was found that the smaller subjects who exercised at the lowest absolute V(E) had significantly smaller responses than did the larger subjects. These results strongly suggest that for the O3 concentrations and exposure durations used in this study, the effect of V(E) on O3-induced FEV1.0 and SS responses is not body-size-dependent.

Adult↗