Influence of menstrual cycle on thermoregulatory, metabolic, and heart rate responses to exercise at night

Abstract

Ten women [mean maximal O2 uptake (VO2max), 2.81 l X min-1] exercised for 15 min on a cycle ergometer in the middle of the luteal phase (L) and in the early follicular phase (F) of the menstrual cycle at the same constant work rates (mean 122 W) and an ambient temperature of 18 degrees C. Serum progesterone averaged 44.7 nmol X l-1 in L and 0.7 nmol X l-1 in F. After a 4-h resting period, exercise was performed between 3 and 4 A.M., when the L-F core temperature difference is maximal. Preexercise esophageal (Tes), tympanic (Tty), and rectal (Tre) temperatures averaged 0.6 degrees C higher in L. During exercise Tes, Tty, and Tre averaged 0.5 degrees C higher. The thresholds for chest sweating and cutaneous vasodilation (heat clearance technique) at the thumb and forearm were elevated in L by an average of 0.47 degrees C, related to mean body temperature (Tb(es) = 0.87Tes + 0.13Tskin), Tes, Tty, or Tre. The above-threshold chest sweat rate and cutaneous heat clearances were also increased in L. The mean exercise heart rate was 170.0 beats X min-1 in L and 163.8 beats X min-1 in F. The mean exercise VO2 in L (2.21 l X min-1) was 5.2% higher than in F (2.10 l X min-1), the metabolic rate was increased in L by 5.6%, but the net efficiency was 5.3% lower. No significant L-F differences in the respiratory exchange ratio and postexercise plasma lactate were demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of the menstrual cycle on performance of intermittent, high-intensity shuttle running in a hot environment

“…The finding of the present study that the performance, rectal temperature, heart rate and perceived exertion of unacclimatised eumennorheic women during intermittent running in the heat (31 ± 0.2 o C; 23.1 ± 0.9% RH) were unaffected by menstrual cycle phase is largely consistent with previous research examining other modes of exercise (Wells and Horvath 1974;Horvath and Drinkwater 1982 temperature between the luteal and follicular phase are observed) in moderate environmental conditions after a 4 h rest period in the heat, rectal temperature, heart rate, sweating thresholds and oxygen uptake were all lower during the follicular in comparison with the luteal phase (Hessemer and Brück 1985). Thus, in the present study, while the similar running performance in the follicular and luteal phases of the cycle is entirely consistent with previous cycling and walking studies, the lack of any effect on deep body temperature or cardiovascular responses may be explained by the unacclimatised status of the subjects and the intense nature of the exercise.…”

Applied Physiology of Female Soccer: An Update

“…VO2max appears to be largely unaffected by the phase of the menstrual cycle [80,81]. However, some studies have shown increased minute ventilation [39,[82][83][84], heart rate [84][85][86] and rating of perceived exertion [84,85] during the luteal phase, which could be attributed to an increased core temperature (0.3 -0.5 °C) during this phase [84]. Lactate threshold findings are equivocal with some reports of stable values throughout the cycle [87,88], whilst others describe lower blood lactate concentrations in the luteal phase during moderate-intensity activity [89].…”

Resting energy expenditure in females with cystic fibrosis: Is it affected by puberty?

“…Some studies measuring REE in healthy female premenopausal adults during the menstrual cycle have described a slight increase (5-9%) in REE in the luteal (Hessemer and Bruck, 1985;Webb, 1986) compared with the follicular phase, although others have shown no difference in REE between the two phases (Howe et al, 1993;Piers et al, 1995). However, the weight of evidence points to cyclical changes in REE during the menstrual cycle (The National Academy of Sciences, 2002).…”