Responses to dry heat of men and women with similar aerobic capacities

1981 ◽  
Vol 50 (1) ◽  
pp. 65-70 ◽  
Author(s):  
A. J. Frye ◽  
E. Kamon
Keyword(s):  
Heat Stress ◽  
Menstrual Cycle ◽  
Strain State ◽  
Sweat Rate ◽  
Stress Tests ◽  
Ambient Conditions ◽  
Men And Women ◽  
Dry Heat ◽  
Before And After ◽  
Cardiovascular Strain

Four men and four women with similar VO2max (56.33 +/- 4.05 and 54.08 +/- 4.27 ml.kg-1.min-1, respectively) exercised up to 3 h at 30% VO2max during heat stress tests (HST) before and after acclimation to dry heat [dry-bulb temperature (Tdb)/wet-bulb temperature (Twb) = 48/25 degrees C]. Rectal (Tre), tympanic sweat on the chest (msw), and total sweat rate (Msw) were recorded. There were no differences in the responses of the women between phases of the menstrual cycle. Tre, Tty, Tsk, and Tdb at the onset of sweating were similar in both sexes before and after acclimation. The nonacclimated men had significantly higher Msw and slower rise in Tre as compared to the nonacclimated women. Following acclimation these differences were no longer evident. Acclimation produced an increase in Msw in both sexes that was characterized by an increase in sweating sensitivity (delta msw/delta Tre). It was concluded that sex alone does not determine responses to heat stress. Consideration should also be given to the relative cardiovascular strain, state of acclimation, and the ambient conditions.

Endogenous hormones subtly alter women's response to heat stress

1988 ◽  
Vol 65 (5) ◽  
pp. 2313-2317 ◽  
Author(s):  
A. J. Carpenter ◽  
S. A. Nunneley
Keyword(s):  
Heat Stress ◽  
Steady State ◽  
Sweat Rate ◽  
Cycle Ergometer ◽  
Endogenous Hormones ◽  
Serum Concentrations ◽  
Stress Tests ◽  
Sweat Loss ◽  
Dry Heat ◽  
Ergometer Exercise

The thermoregulatory responses of menstruant women to exercise in dry heat (dry-bulb temperature/wet-bulb temperature = 48/25 degrees C) were evaluated at three times during the menstrual cycle: menstrual flow (MF), 3-5 days during midcycle including ovulation (OV), and in the middle of the luteal phase (LU). Serum concentrations of estradiol-17 beta (E2), progesterone (Pg), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured by radioimmunoassay, and these values were used to determine the dates of OV (peak LH and FSH) and LU (peak postovulatory Pg). After heat acclimation, subjects received heat stress tests (HST) consisting of a 2-h cycle-ergometer exercise at 30% of maximal O2 consumption in the heat. Rectal (Tre) and mean skin (Tsk) temperatures, heart rate (HR), and sweat rate on the chest and thigh were recorded continuously. Total sweat loss (Msw), as indicated by weight loss, was recorded every 20 min, and equivalent water replacement was given. Steady-state exercise metabolic rate (M) was measured at 45 and 110 min. Seven of eight subjects had ovulatory cycles during experimental months. At rest, Tre was lowest at OV and significantly higher at LU. During steady-state exercise both Tre and Tsk were lowest at OV and significantly higher at LU. There were no differences between phases in Msw, sweat rate on the chest and thigh or M. Despite higher Tre and Tsk at LU, all subjects were able to complete the 2-h of exercise.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypohydration and exercise: effects of heat acclimation, gender, and environment

1983 ◽  
Vol 55 (4) ◽  
pp. 1147-1153 ◽  
Author(s):  
M. N. Sawka ◽  
M. M. Toner ◽  
R. P. Francesconi ◽  
K. B. Pandolf
Keyword(s):  
Aerobic Power ◽  
Sweat Rate ◽  
Heat Rate ◽  
Heat Acclimation ◽  
Experimental Conditions ◽  
Exercise Tests ◽  
Men And Women ◽  
Before And After ◽  
Hot Environments ◽  
Cardiovascular Strain

This study examined the effects of heat acclimation and subject gender on treadmill exercise in comfortable (20 degrees C, 40% rh), hot-dry (49 degrees C, 20% rh), and hot-wet (35 degrees C, 79% rh) environments while subjects were hypo- or euhydrated. Six male and six female subjects, matched for maximal aerobic power and percent body fat, completed two exercise tests in each environment both before and after a 10-day heat acclimation program. One exercise test was completed during euhydration and one during hypohydration (-5.0% from baseline body weight). In general, no significant (P greater than 0.05) differences were noted between men and women at the completion of exercise for rectal temperature (Tre), mean skin temperature (Tsk), or heat rate (HR) during any of the experimental conditions. Hypohydration generally increased Tre and HR values and decreased sweat rate values while not altering Tsk values. In the hypohydration experiments, heat acclimation significantly reduced Tre (0.19 degrees C) and HR (13 beats X min-1) values in the comfortable environment, but only HR values were reduced in hot-dry (21 beats X min-1) and hot-wet (21 beats X min-1) environments. The present findings indicated that men and women respond in a physiologically similar manner to hypohydration during exercise. They also indicated that for hypohydrated subjects heat acclimation decreased thermoregulatory and cardiovascular strain in a comfortable environment, but only cardiovascular strain decreased in hot environments.

Core Temperature and Sweating in Men and Women During a 15-km Race in Cool Conditions

2020 ◽  
Vol 15 (8) ◽  
pp. 1132-1137
Author(s):  
Coen C.W.G. Bongers ◽  
Dominique S.M. ten Haaf ◽  
Nicholas Ravanelli ◽  
Thijs M.H. Eijsvogels ◽  
Maria T.E. Hopman
Keyword(s):  
Body Mass ◽  
Heat Production ◽  
Sweat Rate ◽  
Core Body Temperature ◽  
Whole Body ◽  
Ambient Conditions ◽  
External Work ◽  
Men And Women ◽  
The Impact ◽  
Cool Conditions

Purpose: Studies often assess the impact of sex on the relation between core body temperature (CBT), whole-body sweat rate (WBSR), and heat production during exercise in laboratory settings, but less is known in free-living conditions. Therefore, the authors compared the relation between CBT, WBSR, and heat production between sexes in a 15-km race under cool conditions. Methods: During 3 editions of the Seven Hills Run (Nijmegen, the Netherlands) with similar ambient conditions (8–12°C, 80–95% relative humidity), CBT and WBSR were measured among 375 participants (52% male) before and immediately after the 15-km race. Heat production was estimated using initial body mass and mean running speed, assuming negligible external work. Results: Men finished the race in 76 (12) minutes and women in 83 (13) minutes (P < .001, effect size [ES] = 0.55). Absolute heat production was higher in men than in women (1185 [163] W vs 867 [122] W, respectively, P < .001, ES = 1.47), even after normalizing to body mass (15.0 [2.2] W/kg vs 13.8 [1.9] W/kg, P < .001, ES = 0.56). Finish CBT did not differ between men and women (39.2°C [0.7°C] vs 39.2°C [0.7°C], P = .71, ES = 0.04). Men demonstrated a greater increase in CBT (1.5°C [0.8°C] vs 1.3°C [0.7°C], respectively, P = .013, ES = 0.31); the sex difference remains after correcting for heat production (P = .004). WBSR was larger in men (18.0 [6.9] g/min) than in women (11.4 [4.7] g/min; P < .001, ES = 0.97). A weak correlation between WBSR and heat production was found irrespective of sex (R2 = .395, P < .001). Conclusions: WBSR was associated with heat production, irrespective of sex, during a self-paced 15-km running race in cool environmental conditions. Men had a higher ΔCBT than women.

Protein and carbohydrate supplementation during 5-day aerobic training enhanced plasma volume expansion and thermoregulatory adaptation in young men

2010 ◽  
Vol 109 (4) ◽  
pp. 1247-1255 ◽  
Author(s):  
Masaki Goto ◽  
Kazunobu Okazaki ◽  
Yoshi-ichiro Kamijo ◽  
Shigeki Ikegawa ◽  
Shizue Masuki ◽  
...  
Keyword(s):  
Plasma Volume ◽  
Sweat Rate ◽  
Young Men ◽  
Peak Oxygen Consumption ◽  
Plasma Volume Expansion ◽  
Carbohydrate Supplementation ◽  
Before And After ◽  
Forearm Vascular Conductance ◽  
Cardiovascular Strain ◽  
Cardiac Stroke Volume

We examined whether protein and carbohydrate (CHO) supplementation during 5-day training enhanced plasma volume (PV) expansion and thermoregulatory and cardiovascular adaptations in young men. Eighteen men [age 23 ± 4 (SD) yr] were divided into two groups according to supplements: placebo (CNT: 0.93 kcal/kg, 0.00 g protein/kg, n = 9) and protein and CHO (Pro-CHO: 3.6 kcal/kg, 0.36 protein/kg, n = 9). Subjects in both groups performed a cycling exercise at 70% peak oxygen consumption rate (V̇o2peak), 30 min/day, for 5 consecutive days at 30°C ambient temperature and 50% relative humidity and took either a placebo or Pro-CHO within 10 min after exercise for each day. Before and after training, PV at rest, heart rate (HR), and esophageal temperature (Tes) during 30-min exercise at 65% of pretraining V̇o2peak in the same condition as training were determined. Also, the sensitivity of the chest sweat rate (ΔSR/ΔTes) and forearm vascular conductance (ΔFVC/ΔTes) in response to increased Tes were determined. After training, PV and cardiac stroke volume (SV) at rest increased in both groups ( P < 0.001) but the increases were twofold higher in Pro-CHO than CNT ( P = 0.007 and P = 0.078, respectively). The increases in HR from 5 to 30 min and Tes from 0 to 30 min of exercise were attenuated after training in both groups with greater attenuation in Pro-CHO than CNT ( P = 0.002 and P = 0.072, respectively). ΔSR/ΔTes increased in CNT ( P = 0.052) and Pro-CHO ( P < 0.001) and the increases were higher in Pro-CHO than CNT ( P = 0.018). ΔFVC/ΔTes increased in Pro-CHO ( P < 0.001), whereas not in CNT ( P = 0.16). Thus protein-CHO supplementation during 5-day training enhanced PV expansion and thermoregulatory adaptation and, thereby, the reduction in heat and cardiovascular strain in young men.

scholarly journals Lactational Responses of Heat-Stressed Dairy Goats to Dietary L-Carnitine Supplementation

Animals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 567 ◽  
Author(s):  
Mehaba ◽  
Salama ◽  
Such ◽  
Albanell ◽  
Caja
Keyword(s):  
Heat Stress ◽  
Milk Production ◽  
Feed Intake ◽  
Subcutaneous Fat ◽  
Latin Square ◽  
Acid Oxidation ◽  
Carnitine Supplementation ◽  
Ambient Conditions ◽  
Dairy Goats ◽  
Before And After

Heat stress causes significant losses in milk production, and nutritional strategies are needed to alleviate its effects. Endogenous carnitine synthesis is also reduced by heat stress (HS). Carnitine plays a central role in fatty acid oxidation and buffers the toxic effects of acyl groups. We hypothesized that carnitine supplementation would make up for any carnitine deficiencies during HS and improve lipid metabolism. The objective was to evaluate rumen-protected L-carnitine (CAR) supplementation in dairy goats under thermo-neutral (TN) or HS conditions. Four Murciano-Granadina dairy goats were used in a four × four Latin square design. Goats were allocated to one of four treatments in a two × two factorial arrangement. Factors were 1) diet: control (CON) or supplementation with CAR (1 g/d); and 2) ambient conditions: TN (15 to 20 °C) or HS (0900 to 2100 h at 35 °C, 2100 to 0900 h at 28 °C). Blood free-, acetyl-, and total-carnitine concentrations increased almost three times by supplementation. Despite this efficient absorption, CAR had no effect on feed intake, milk production or blood metabolites in TN or HS conditions. Heat stress increased rectal temperature and respiratory rate. Additionally, HS goats experienced 26% loss in feed intake, but they tended to eat longer particle sizes. Compared to TN, heat-stressed goats lost more subcutaneous fat (difference in fat thickness measured before and after each period = −0.72 vs. +0.64 mm). In conclusion, supplemented L-carnitine was efficiently absorbed, but it had no lactational effects on performance of goats under thermo-neutral or heat stress conditions.

Pubertal Induction of Sweat Gland Activity

1981 ◽  
Vol 60 (6) ◽  
pp. 689-692 ◽  
Author(s):  
J. Rees ◽  
S. Shuster
Keyword(s):  
Gene Expression ◽  
Sweat Gland ◽  
Sweat Rate ◽  
Adult Life ◽  
Men And Women ◽  
Normal People ◽  
Sweat Production ◽  
Before And After ◽  
Prepubertal Boys ◽  
The Difference

1. To study the difference in sweat rate between men and women the rates of cholinergic-induced sweating were measured in normal people before and after puberty and in response to androgens and anti-androgens. 2. Sweat rate in men was more than double that in women. 3. This difference did not occur in prepubertal boys and girls in whom the rate, corrected for surface area, was comparable with that in women. 4. Application or injection of androgen locally did not stimulate sweat production in the adult female. 5. Anti-androgen topically or systemically did not decrease sweat rate in men. 6. It is concluded that the rate of sweat rate in men is caused by androgen-induced gene expression at puberty and not by androgen modulation in adult life.

PENGARUH TERAPI TERTAWA TERHADAP PENURUNAN TEKANAN DARAH LANSIA DI UPT PANTI WREDHA BUDHI DHARMA YOGYAKARTA

2019 ◽  
Vol 13 (1) ◽  
Author(s):  
Niken Setyaningrum ◽  
Andri Setyorini ◽  
Fachruddin Tri Fitrianta
Keyword(s):  
Blood Pressure ◽  
Data Analysis ◽  
The Elderly ◽  
Control Group ◽  
Group Comparison ◽  
Control Blood Pressure ◽  
Men And Women ◽  
Treatment Of Hypertension ◽  
Before And After ◽  
The Difference

ABSTRACTBackground: Hypertension is one of the most common diseases, because this disease is suffered byboth men and women, as well as adults and young people. Treatment of hypertension does not onlyrely on medications from the doctor or regulate diet alone, but it is also important to make our bodyalways relaxed. Laughter can help to control blood pressure by reducing endocrine stress andcreating a relaxed condition to deal with relaxation.Objective: The general objective of the study was to determine the effect of laughter therapy ondecreasing elderly blood pressure in UPT Panti Wredha Budhi Dharma Yogyakarta.Methods: The design used in this study is a pre-experimental design study with one group pre-posttestresearch design where there is no control group (comparison). The population in this study wereelderly aged over> 60 years at 55 UPT Panti Wredha Budhi Dharma Yogyakarta. The method oftaking in this study uses total sampling. The sample in this study were 55 elderly. Data analysis wasused to determine the difference in blood pressure before and after laughing therapy with a ratio datascale that was using Pairs T-TestResult: There is an effect of laughing therapy on blood pressure in the elderly at UPT Panti WredhaBudhi Dharma Yogyakarta marked with a significant value of 0.000 (P <0.05)

scholarly journals Effects of cooled floor pads combined with chilled drinking water on behavior and performance of lactating sows under heat stress

2021 ◽  
Vol 99 (3) ◽  
Author(s):  
Y Zhu ◽  
L J Johnston ◽  
M H Reese ◽  
E S Buchanan ◽  
J E Tallaksen ◽  
...  
Keyword(s):  
Drinking Water ◽  
Heat Stress ◽  
Respiration Rate ◽  
Rectal Temperature ◽  
Time Budget ◽  
Video Recording ◽  
Lactating Sows ◽  
Before And After ◽  
And Performance ◽  
Drinking Frequency

Abstract This study was conducted to evaluate whether cooled floor pads combined with chilled drinking water could alleviate negative impacts of heat stress on lactating sows. Thirty sows (Landrace × Yorkshire, Parity = 1 to 6) were housed in individual farrowing stalls in two rooms with temperatures being controlled at 29.4°C (0700–1900 hours) and 23.9°C (1900–0700 hours). Sows in one room (Cool), but not in the other room (Control) were provided cooled floor pads (21–22°C) and chilled drinking water (13–15°C). Behavior of sows (15 sows/treatment) was video recorded during farrowing, and days 1, 3, 7, 14, and 21 after farrowing. Videos were viewed continuously to register the birth time of each piglet, from which total farrowing duration and birth intervals were calculated. The number of drinking bouts and the duration of each drinking bout were registered for each sow through viewing videos continuously for 2 h (1530–1730 hours) each video-recording day. Postures (lying laterally, lying ventrally, sitting, and standing) were recorded by scanning video recordings at 5-min intervals for 24 h each video-recording day, and time budget for each posture was calculated. Rectal temperature and respiration rate were measured for all sows the day before and after farrowing, and then once weekly. Sow and litter performance was recorded. Data were analyzed using the Glimmix procedure of SAS. The cooling treatment did not affect sow behavior or litter performance. Sows in the Cool room had lower rectal temperature (P = 0.03) and lower respiration rate (P &lt; 0.001), consumed more feed (P = 0.03), tended to have reduced weight loss (P = 0.07), and backfat loss (P = 0.07) during lactation than sows in the Control room. As lactation progressed, sows increased drinking frequency (P &lt; 0.001) and time spent lying ventrally (P &lt; 0.0001), standing (P &lt; 0.001), and sitting (P &lt; 0.0001), and decreased time spent lying laterally (P &lt; 0.0001) in both Cool and Control rooms. While cooled floor pads combined with chilled drinking water did not affect sow behavior, they did alleviate heat stress partially, as indicated by decreased rectal temperature, respiration rate, weight, and backfat loss, and increased feed intake in lactating sows.

scholarly journals Body Image and Voluntary Gaze Behaviors towards Physique-Salient Images

2021 ◽  
Vol 18 (5) ◽  
pp. 2549
Author(s):  
April Karlinsky ◽  
Holly Howe ◽  
Melissa de Jonge ◽  
Alan Kingstone ◽  
Catherine M. Sabiston ◽  
...  
Keyword(s):  
Body Image ◽  
Media Consumption ◽  
Negative Consequences ◽  
Body Appreciation ◽  
Men And Women ◽  
Physical Strength ◽  
Adult Men ◽  
Self Perceptions ◽  
Before And After ◽  
Image Variables

The purpose of this study was to explore body image correlates of voluntary consumption of physique-salient media. A secondary aim was to assess changes in affect following media consumption. Young adult men (n = 47; mean age = 20.2 years) and women (n = 87; mean age = 19.5 years) were discretely exposed to images of same-sex models with idealized- and average-physiques while completing an irrelevant computer task. Voluntary gaze at the images was covertly recorded via hidden cameras. Participants also completed measures of affect before and after the computer task. Measures of body-related envy, body appreciation, and self-perceptions of attractiveness, thinness, and physical strength were completed. Men and women did not differ in how often nor for how long they looked at the images overall, but body image variables were differentially associated with their voluntary gaze behaviors. For men, higher body-related envy and lower body appreciation were correlated with more looks at the average-physique model. Although women reported higher body-related envy than men, envy and body appreciation were not significant correlates of gaze behaviors for women. Both men and women experienced a general affective decrease over time, but only for men was the change in negative affect associated with their time spent looking at the ideal-physique image. Overall, these findings suggest that body-related envy and body appreciation influence how men choose to consume physique-salient media, and that media consumption may have negative consequences for post-exposure affect. Body image factors appear to be more strongly associated with behavior in men, perhaps because men are generally less often exposed to physique-salient media and, in particular, to average-physique images.

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