PMID- 33330586
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20201218
IS  - 2296-861X (Print)
IS  - 2296-861X (Electronic)
IS  - 2296-861X (Linking)
VI  - 7
DP  - 2020
TI  - Caffeine Timing Improves Lower-Body Muscular Performance: A Randomized Trial.
PG  - 585900
LID - 10.3389/fnut.2020.585900 [doi]
LID - 585900
AB  - Little is known about the optimal time to consume caffeine prior to exercise to 
      maximize the ergogenic benefits of the substance. Purpose: To determine the 
      optimal pre-exercise time interval to consume caffeine to improve lower-body 
      muscular performance. A secondary aim was to identify the presence of any sex 
      differences in responses to timed caffeine administration. Methods: Healthy, 
      resistance-trained males (n = 18; Mean+/-SD; Age: 25.1 +/- 5.7 years; Height: 178.4 +/- 
      7.1 cm; Body mass: 91.3 +/- 13.5 kg; Percent body fat: 20.7 +/- 5.2; Average caffeine 
      consumption: 146.6 +/- 100.3 mg/day) and females (n = 11; Mean +/- SD; Age: 20.1 +/- 
      1.6 years; Height: 165.0 +/- 8.8 cm; Body mass: 65.8 +/- 10.0 kg; Percent bodyfat: 
      25.8 +/- 4.2; Average caffeine consumption: 111.8 +/- 91.7 mg/day) participated in 
      this investigation. In a randomized, double-blind, placebo-controlled, crossover 
      fashion, participants consumed 6 mg.kg(-1) caffeine or placebo solution at three 
      time points: 2 h prior (2H), 1 h prior (1H), or 30 min prior (30M) to exercise 
      testing. During three visits, caffeine was randomly administered at one time 
      point, and placebo was administered at the other two time points. During one 
      visit, placebo was administered at all three time points. Next, participants 
      performed isometric mid-thigh pulls (IMTP), countermovement vertical jumps 
      (CMVJ), and isometric/isokinetic knee extensor testing (ISO/ISOK). Results: 
      Caffeine administered at 1H significantly improved absolute CMVJ and ISO 
      performance relative to placebo. Mean CMVJ jump height was significantly higher 
      during 1H compared to 30M. However, only caffeine administered at 30M 
      significantly improved absolute measures of isokinetic performance. Analysis of 
      the pooled caffeine conditions revealed that muscular performance was more 
      consistently augmented by caffeine in males compared to females. Conclusions: 
      Pre-exercise caffeine timing significantly modulated participant responses to the 
      substance, with 1H exerting the most consistent ergogenic benefits relative to 
      other time points, particularly compared to 2H. Male participants were found to 
      respond more consistently to caffeine compared to female participants. These 
      results suggest that active individuals can maximize the ergogenic effects of 
      caffeine by consuming the substance ~1 h prior to the point when peak muscular 
      performance is desired.
CI  - Copyright (c) 2020 Harty, Zabriskie, Stecker, Currier, Tinsley, Surowiec, Jagim, 
      Richmond and Kerksick.
FAU - Harty, Patrick S
AU  - Harty PS
AD  - Exercise and Performance Nutrition Laboratory, School of Health Sciences, 
      Lindenwood University, St. Charles, MO, United States.
AD  - Energy Balance and Body Composition Laboratory, Department of Kinesiology & Sport 
      Management, Texas Tech University, Lubbock, TX, United States.
FAU - Zabriskie, Hannah A
AU  - Zabriskie HA
AD  - Exercise and Performance Nutrition Laboratory, School of Health Sciences, 
      Lindenwood University, St. Charles, MO, United States.
FAU - Stecker, Richard A
AU  - Stecker RA
AD  - Exercise and Performance Nutrition Laboratory, School of Health Sciences, 
      Lindenwood University, St. Charles, MO, United States.
FAU - Currier, Brad S
AU  - Currier BS
AD  - Exercise and Performance Nutrition Laboratory, School of Health Sciences, 
      Lindenwood University, St. Charles, MO, United States.
FAU - Tinsley, Grant M
AU  - Tinsley GM
AD  - Energy Balance and Body Composition Laboratory, Department of Kinesiology & Sport 
      Management, Texas Tech University, Lubbock, TX, United States.
FAU - Surowiec, Kazimierz
AU  - Surowiec K
AD  - Mass Spectrometry Facility, Department of Chemistry & Biochemistry, Texas Tech 
      University, Lubbock, TX, United States.
FAU - Jagim, Andrew R
AU  - Jagim AR
AD  - Sports Medicine, Mayo Clinic Health System, Onalaska, WI, United States.
FAU - Richmond, Scott R
AU  - Richmond SR
AD  - Exercise and Performance Nutrition Laboratory, School of Health Sciences, 
      Lindenwood University, St. Charles, MO, United States.
FAU - Kerksick, Chad M
AU  - Kerksick CM
AD  - Exercise and Performance Nutrition Laboratory, School of Health Sciences, 
      Lindenwood University, St. Charles, MO, United States.
LA  - eng
PT  - Journal Article
DEP - 20201123
PL  - Switzerland
TA  - Front Nutr
JT  - Frontiers in nutrition
JID - 101642264
PMC - PMC7719671
OTO - NOTNLM
OT  - caffeine
OT  - nutrient timing
OT  - performance
OT  - power
OT  - strength
EDAT- 2020/12/18 06:00
MHDA- 2020/12/18 06:01
PMCR- 2020/01/01
CRDT- 2020/12/17 05:54
PHST- 2020/07/21 00:00 [received]
PHST- 2020/10/28 00:00 [accepted]
PHST- 2020/12/17 05:54 [entrez]
PHST- 2020/12/18 06:00 [pubmed]
PHST- 2020/12/18 06:01 [medline]
PHST- 2020/01/01 00:00 [pmc-release]
AID - 10.3389/fnut.2020.585900 [doi]
PST - epublish
SO  - Front Nutr. 2020 Nov 23;7:585900. doi: 10.3389/fnut.2020.585900. eCollection 
      2020.