PMID- 37699150
OWN - NLM
STAT- MEDLINE
DCOM- 20231216
LR  - 20231216
IS  - 1530-0315 (Electronic)
IS  - 0195-9131 (Linking)
VI  - 56
IP  - 1
DP  - 2024 Jan 1
TI  - Fatigue Resistance Is Altered during the High-Hormone Phase of Eumenorrheic 
      Females but Not Oral Contraceptive Users.
PG  - 92-102
LID - 10.1249/MSS.0000000000003289 [doi]
AB  - PURPOSE: This study aimed to examine the effect of ovarian hormones and their 
      synthetic equivalents on substrate utilization and fatigue resistance during a 
      race-specific cycling protocol. METHODS: Seventeen well-trained female cyclists 
      (nine eumenorrheic females, eight oral contraceptive users) completed two 
      experimental trials, in a randomized order, in their low- (follicular/sugar pill) 
      and high-hormone (luteal/active pill) phases. Each 91-min trial consisted of a 
      45-min moderate-intensity component (submaximal cycling, or SMC) followed by 6 
      min of high-intensity (HIT) and then a fatigue resistance test (FRT): 6 x 1-min 
      all-out efforts with 1-min active recovery. Meals, comprising carbohydrate (CHO) 
      intake of 8 g.kg -1 body mass, were standardized 24-h pretrial. An 
      electrolyte-only solution was provided ad libitum during each trial. RESULTS: In 
      eumenorrheic females, a large reduction in average power during FRT was observed 
      in the luteal phase (277 +/- 31 vs 287 +/- 33 W; P = 0.032). Greater CHO ox (~ 4%, P 
      = 0.020) during SMC and ventilatory inefficiencies during SMC and HIT (~7%, P < 
      0.001) were also observed in the luteal phase. In contraceptive users, despite 
      some phasal changes in cardiorespiratory and metabolic data in SMC (~6% higher 
      blood glucose and ~2% higher minute ventilation in active pill phase), none of 
      the performance parameters in the FRT were different. CONCLUSIONS: Fatigue 
      resistance was compromised only in high-hormone phase of the menstrual cycle, 
      with eumenorrheic females likely susceptible because of increased CHO utilization 
      during SMC. Hormone-induced ventilatory inefficiencies may also have increased 
      metabolic demand. These findings emphasize the need to maintain CHO availability 
      for power production, particularly in high-hormone phases.
CI  - Copyright (c) 2023 by the American College of Sports Medicine.
FAU - Lee, Serene J L
AU  - Lee SJL
FAU - Sim, Marc P
AU  - Sim MP
FAU - VAN Rens, Fleur E C A
AU  - VAN Rens FECA
AD  - Discipline of Exercise Science, Murdoch University, Perth, Western Australia, 
      AUSTRALIA.
FAU - Peiffer, Jeremiah J
AU  - Peiffer JJ
LA  - eng
PT  - Journal Article
DEP - 20230829
PL  - United States
TA  - Med Sci Sports Exerc
JT  - Medicine and science in sports and exercise
JID - 8005433
RN  - 0 (Hormones)
SB  - IM
MH  - Humans
MH  - Female
MH  - *Menstrual Cycle
MH  - *Luteal Phase
MH  - Hormones
EDAT- 2023/09/12 18:41
MHDA- 2023/12/17 09:43
CRDT- 2023/09/12 15:43
PHST- 2023/12/17 09:43 [medline]
PHST- 2023/09/12 18:41 [pubmed]
PHST- 2023/09/12 15:43 [entrez]
AID - 00005768-990000000-00348 [pii]
AID - 10.1249/MSS.0000000000003289 [doi]
PST - ppublish
SO  - Med Sci Sports Exerc. 2024 Jan 1;56(1):92-102. doi: 10.1249/MSS.0000000000003289. 
      Epub 2023 Aug 29.