摘要:

RANSFORD, CHARLES P. A role for amines in the antidepressant effect of exercise.Med. Sci. Sports Exercise,Vol. 14, No. 1. pp. 1–10, 1982. A review of the literature suggests that exercise may have antidepressant effects and, like other treatments for depression such as electroconvulsive therapy (ECT), antidepressant medication, and REM sleep deprivation, may enhance aminergic synaptic transmission in the central nervous system. In addition, the effects of exercise and other antidepressants on sleep are similar. Therefore, it is suggested that exercise is an antidepressant that enhances aminergic synaptic transmission in the central nervous system. Many more psychological and physiological studies must be performed in order to verify and quantify this relationship. Present statements that single out norepinephrine, dopamine, or serotonin as the crucial amine may be premature and oversimplified. Future physiological studies must take into consideration the advantages and disadvantages of human and animal subjects. Future psychological studies should be attentive to possible differences in psychological benefits between normal and depressed subjects and should not neglect the possible role of cognitive factors such as subjects' attitudes towards exercising or the feelings of accomplishment that may result from increased physical fitness. There is also a need to measure antidepressant effects in long-term exercise programs and in studies employing various forms of exercise.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

MARKOFF, RICHARD A., PAUL RYAN, and TED YOUNG. Endorphins and mood changes in long-distance running.Med. Sci. Sports Exercise,Vol. 1–4, No. 1, pp. 11–15, 1982. Acute and chronic positive mood changes have been said to occur with running and jogging. It has been suggested that endogenous substances with opioid activity (endorphins) may serve as modulators of mood. The authors report experiments in which mood changes associated with long-distance running were measured by pre- and post-run difference—scores on a mood adjective checklist, the Profile of Mood States (POMS). Following this, the narcotic antagonist, naloxone, was given subcutaneously in double-blind fashion. The dose was 0.8 mg. The POMS was again presented 15 min later, and post-run/post-injection difference scores were obtained. No naloxone effect was found. The failure of naloxone to reverse the running-associated mood shift indicates that endorphins are not involved. The authors discuss the possible physiologic role of endorphins in light of these and other findings.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

WIRTH, J.C. and T.G. LOHMAN. The relationship of static muscle (unction to use of oral contraceptives.Med. Sci. Sports Exercise,Vol. 14, No. 1, pp. 16–20, 1982. The handgrip endurance time (ET) and total force output (FO) at 50% maximum voluntary contraction (MVC) of 26 females (18–33 yr) were measured during the follicular phase (day 8 ± 2) and luteal phase (day 21 ± 3) of one menstrual cycle. Three groups were utilized: 1) normals (non-users of oral contraceptive agents [OCA]); 2) users of OCA only (users of OCA but not vitamin B-6); and 3) users of OCA and vitamin B-6. Vitamin B-6 status was assessed by measurement of 24-h urine xanthurenic acid (XA) excretion following a 2-g loading dose of L-tryptophan. Recent vitamin B-6 intake was assessed by measurement of 24-h urine 4-pyridoxic acid (4-PA) excretion. There were no significant among-group differences in MVC, however, MVC during the follicular phase was significantly (P< 0.05) greater than during the luteal phase. The ET and FO of normal subjects was significantly (P< 0.05) greater than that of the combined group of users of OCA only, and users of OCA and vitamin B-6. There was no significant difference between users of OCA only and users of OCA and vitamin B-6 in either ET or FO, nor between the follicular and luteal phases of the menstrual cycle. Levels of 4-PA confirmed that the subjects who reported being users of OCA and vitamin B-6 had substantially larger intakes of vitamin B-6 than did the other subjects. Levels of XA indicated that only two subjects, both users of OCA only, were vitamin B-6 deficient. Compared to other users of OCA only, the mean MVC of the vitamin B-6 deficient subjects was lower, the mean ET higher, and the mean FO approximately equal. Therefore, we have concluded that users of OCA appear to exhibit lower static muscle endurance than normal subjects, and their vitamin B-6 status was not a mediating factor.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

KATCH, VICTOR L., STANLEY S. SADY, and PATTY FREEDSON. Biological variability in maximum aerobic power.Med. Sci. Sports Exercise,Vol. 14, No. 1, pp. 21–25, 1982. The biological variation in maximum aerobic power (V O2max) was examined in four trained females and one trained male. An average of 8–20 repeat VO2max) treadmill tests over a 2–4 wk period were performed on each subject (80 total tests). Biological variation (Si) in VO2max) was computed as the standard deviation for the VO2max) values for each individual, after subtracting net technological error (Se). Technological error was computed for each piece of equipment as the standard deviation of multiple trials. Results revealed that Si+ Seamounted to ± 5.6%. Biological variability accounted for 90% or more of this variability, while technological error accounted for less than 10%. In light of the magnitude of biological variation for VO2max), the necessity for securing control data when attempting to study training effects is pointed out.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

QUIRK, JOHN E. and WAYNE E. SINNING. Anaerobic and aerobic responses of males and females to rope skipping.Med. Sci. Sports Exercise,Vol. 14, No. 1, pp. 26–29, 1982. Six male and six female subjects performed maximal bicycle ergometer work and skipped rope at selected rates. Measures included oxygen uptake (Vo2), oxygen debt (VO2debt), blood lactate, and heart rate (HR). Mean values for males for the maximum test and while skipping at 120, 140, and 160 turns min-1were, respectively: VO2-50.2, 38.3, 39.7, and 44.3 ml.kg-1.min-1; HR-185, 166, 168, and 178 beats.min-1; VO2debt—570, 3.65, 3.50, and 4.04 liter; and lactate—12.7, 7.4, 7.6, and 9.2 mM·l-1. For females: VO2—42.8, 39.8, 39.4, and 39.4 ml.kg-1.min-1; HR—185, 181, 181, and 181 beats.min-1; VO2debt—4.71, 4.27, 4.22, and 4.15 liter; and lactate—11.5, 11.5, 12.2, and 11.9 mM·l-1. No significant differences were found between treatments for females for any measure. Rope skipping placed high demands on both aerobic (females, 92% VO2max), males, 76–88%) and anaerobic capacities (females, 100–106% lactate values after maximum bicycle exercise; males, 58–72%). In males, who did not reach VO2max) during rope skipping, it was verified that the VO2requirement does not increase with skipping rate over a relatively wide range, but that extremely high rates do require more energy from both aerobic and anaerobic sources. Differences in tolerance of males and females to rope skipping were attributed to the lower aerobic power and higher body fat of females.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

CAVANAGH, PETER R. and KEITH R. WILLIAMS. The effect of stride length variation on oxygen uptake during distance running.Med. Sci. Sports Exercise,Vol. 14, No. 1, pp. 30–35, 1982. Ten recreational runners (mean VO2max) 64.7 ml.kg-1.min-1) underwent a 5-d acclimation period to treadmill running at a 7 min.mile-1pace (3.83 m.s-1) for 30 min each day. During these runs their freely chosen stride lengths were determined and expressed as a percentage of leg length (%LL). On two subsequent testing days stride length was systematically varied over a range of ± 20% LL about the freely chosen value. O2uptake was determined by the Douglas Bag method. All subjects exhibited a stride length at which O2uptake was minimized, although the individual profiles varied considerably. The mean increases in VO2were 2.6 and 3.4 ml.kg-1.min-1at the short-and long-stride length extremes, respectively. During unrestricted running deviations from optimal stride length caused a mean increase in VO2of 0.2 ml.kg-1.min-1. The relatively efficient running patterns used by the subjects during unrestricted running indicate either an adaption to the chosen stride length through training or a successful process of energy optimization.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

SQUIRES, RAY W. and E.R. BUSKIRK. Aerobic capacity during acute exposure to simulated altitude, 914 to 2286 meters.Med. Sci. Sports Exercise,Vol. 14, No. 1, pp. 36–40, 1982. In order to systematically assess the effects of acute exposure to moderate hypoxia on aerobic capacity (VO2max), 12 men (regular participants in recreational distance running) performed six treadmill-graded exercise tests (GXTs) in a hypobaric chamber. GXTs 1 and 6 were performed at ambient (control) altitude (362 m, barometric pressure=730 mmHg). GXTs 2–5 were administered during 1–2 h of exposure to barometric pressures of 681, 656, 632, and 574 mmHg simulating altitudes of 914, 1219, 1524, and 2286 m, respectively, with the order of presentation randomized and blinded for each subject. The mean VO2max) for GXTs 1 and 6 (control altitude) were essentially identical with a test-retest correlation of r=0.92. During peak exercise, HR max was unchanged by hypoxia, while VO2max) was significantly lower than the control by 4.8, 6.9, and 11.9% at 1219, 1524, and 2286 m, respectively. SaO2max percent during maximal exercise was significantly reduced from the control by 3.5, 3.6, 7.0, and 11.6% at 914, 1219, 1524, and 2286 m, respectively. It was concluded that VO2max), in physically well-conditioned persons living at 362 m, is reduced during acute exposure to 1219 m and above.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

HAYMES, EMILY M, ARTHUR L. DICKINSON, NANCY MALVILLE, and ROBERT W. ROSS. Effects of wind on the thermal and metabolic responses to exercise in the cold.Med. Sci. Sports Exercise,Vol. 14, No. 1, pp. 41–45, 1982. The thermal and metabolic responses to exercise were studied in a cold environment with and without a wind. Six men and two women rode a cycle ergometer for 90 min at 55–60% VO2max) in a −20°C environment. Subjects were exposed to a 4.1 m.s-1wind on two of the four exposures. The subjects wore regulation cross-country ski uniforms. An additional vest was worn on 2 d, 1 d with the wind and 1 d without the wind. Total insulation for the ski uniform (Icl+awas 1.59 clo and 1.77 clo with the vest. Final Tre, Tsk, and Tbwere significantly lower, and radiative and convective heat loss, heat lost from body storage, and tissue insulation (Il) were significantly greater when exercising in the wind. The addition of the vest increased only Tsk. Both metabolic rate and heart rate increased significantly during exercise, but no significant differences were observed between wind and no-wind conditions. The subjects responded to the increased cooling effect of the wind by increasing It, however, this response was not sufficient to prevent loss of stored heat and Trefrom falling. It was concluded that the exercise intensity must be 10 METS or greater to maintain thermal balance when exercising in a −20°C environment with a 4.1 m.s-1wind if Icl+a= 1.59 clo.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

COHEN, JUDITH S. and CARL V. GISOLFI. Effects of interval training on work-heat tolerance of young women.Med. Sci. Sports Exercise,Vol. 14, No. 1, pp. 46–52, 1982. The purpose of this study was to determine (a) if women could improve their heat tolerance for more than 2 h of a standard test and (b) the effect of training on heat acclimation (ACCL). Six women (experimental group) ages 19 ± 0.8 yr attempted a standard heat tolerance test (HTT) consisting of a 4-h treadmill walk at 30–35% VO2maxin dry heat (45/24°C db/wb, wind velocity 1.22 m/s) before (HTT-I) and after (HTT-II) 11 wk of interval training, and after heat acclimation (HTT-III). A sedentary control group (N=6) matched for age, body weight/surface area, and initial VO2max, performed the same tests but were not trained. ACCL consisted of eight consecutive exposures to the HTT; the eighth exposure served as HTT-III. Training consisted of 90-s treadmill runs at approximately 95% max heart rate (HR) alternated with 60-s rest intervals for 30 min/d (first 2 wk) to 60 min/d (last 9 wk), 4 d/wk in a cool (22°C) environment. Mean rectal temperature (Tre) rose to 39°C, sweat rate (SR) rose to 440 g(m2.h)-1, and VO2maxincreased 11% (P< 0.05) after the 11-wk interval training program. During HTT-I, the ratio of terminal Tre/tolerance time (used as a measure of heat tolerance) averaged 36.6°C/h for both groups. During HTT-II, this ratio averaged 38 ± 17 and 15 ± 12 for control and experimental groups, respectively; mean performance time was 1.2 ± 0.6 and 3.3 ± 1.3 h, respectively. During HTT-III, five of the six trained subjects, but only one of the six control subjects, achieved thermal equilibrium. Thus, young women who trained in a cool environment for a total of 40 h (spread over 11 wk) were able to (a) work at 30–35% VO2maxfor more than 3 h in dry heat, and (b) acclimate to the heat in less time than untrained controls.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

SHARP, RICK L., JOHN P. TROUP, and DAVID L. COSTILL. Relationship between power and sprint freestyle swimming.Med. Sci. Sports Exercise,Vol. 14, No. 1, pp. 53–56, 1982. In an effort to determine the role played by power in sprint swimming, 40 competitive swimmers (22 females and 18 males) were tested for arm power at velocities ranging from 1.60–3.28 m.s-1using an apparatus that was specifically designed to mimic the arm action during swimming. Measurements were also made to determine the contribution of fatigability to sprint swimming performance. In addition, each swimmer performed a series of 25-yd (22.86 m) freestyle sprints. A close relationship was found between power output and sprint swimming performance (r=0.90). The highest power recordings were obtained at test velocities of 2.05 and 2.66 m.s-1, with the average velocity required for peak power being 2.40 m.s-1. This point is referred to as the optimal velocity. Four detrained swimmers were tested before and after 4 wk of isokinetic strength training only. On the average, performance improved 3.76%, while arm power increased by 18.66%. The fatigability of the competitive swimmers was not related to their sprint ability (r=0.01). It is concluded that power, as measured in this study, offers an objective assessment of a component essential for success in sprint swimming.

ISSN:0195-9131    

出版商:OVID    

年代:1982

数据来源: OVID