PMID- 38059288
OWN - NLM
STAT- MEDLINE
DCOM- 20240115
LR  - 20240115
IS  - 1522-1601 (Electronic)
IS  - 0161-7567 (Linking)
VI  - 136
IP  - 1
DP  - 2024 Jan 1
TI  - Assessing exogenous carbohydrate intake needed to optimize human endurance 
      performance across sex: insights from modeling runners pursuing a sub-2-h 
      marathon.
PG  - 158-176
LID - 10.1152/japplphysiol.00521.2023 [doi]
AB  - Carbohydrate (CHO) availability sustains high metabolic demands during prolonged 
      exercise. The adequacy of current CHO intake recommendations, 30-90 g.h(-1) 
      dependent on CHO mixture and tolerability, to support elite marathon performance 
      is unclear. We sought to scrutinize the current upper limit recommendation for 
      exogenous CHO intake to support modeled sub-2-h marathon (S2M) attempts across 
      elite male and female runners. Male and female runners (n = 120 each) were 
      modeled from published literature with reference characteristics necessary to 
      complete a S2M (e.g., body mass and running economy). Completion of a S2M was 
      considered across a range of respiratory exchange rates, with maximal starting 
      skeletal muscle and liver glycogen content predicted for elite male and female 
      runners. Modeled exogenous CHO bioavailability needed for male and female runners 
      were 93 +/- 26 and 108 +/- 22 g.h(-1), respectively (P < 0.0001, d = 0.61). Without 
      exogenous CHO, males were modeled to deplete glycogen in 84 +/- 7 min, females in 
      71 +/- 5 min (P < 0.0001, d = 2.21) despite higher estimated CHO oxidation rates in 
      males (5.1 +/- 0.5 g.h(-1)) than females (4.4 +/- 0.5 g.h(-1); P < 0.0001, d = 1.47). 
      Exogenous CHO intakes </= 90 g.h(-1) are insufficient for 65% of modeled runners 
      attempting a S2M. Current recommendations to support marathon performance appear 
      inadequate for elite marathon runners but may be more suitable for male runners 
      in pursuit of a S2M (56 of 120) than female runners (28 of 120).NEW & NOTEWORTHY 
      This study scrutinizes the upper limit of exogenous carbohydrate (CHO) 
      recommendations for elite male and female marathoners by modeling sex-specific 
      needs across an extreme metabolic challenge lasting  approximately 2 h, a sub-2-h marathon. 
      Contemporary nutritional guidelines to optimize marathon performance appear 
      inadequate for most elite marathon runners but appear more appropriate for males 
      over their female counterparts. Future research examining possible benefits of 
      exogenous CHO intakes > 90 g.h(-1) should prioritize female athlete study 
      inclusion.
FAU - Lukasiewicz, Cole J
AU  - Lukasiewicz CJ
AD  - Department of Human Physiology & Nutrition, College of Nursing and Health 
      Sciences, University of Colorado Colorado Springs (UCCS), Colorado Springs, 
      Colorado, United States.
AD  - William J. Hybl Sports Medicine and Performance Center, Colorado Springs, 
      Colorado, United States.
FAU - Vandiver, Kayla J
AU  - Vandiver KJ
AD  - Department of Human Physiology & Nutrition, College of Nursing and Health 
      Sciences, University of Colorado Colorado Springs (UCCS), Colorado Springs, 
      Colorado, United States.
AD  - William J. Hybl Sports Medicine and Performance Center, Colorado Springs, 
      Colorado, United States.
FAU - Albert, Elizabeth D
AU  - Albert ED
AD  - Department of Human Physiology & Nutrition, College of Nursing and Health 
      Sciences, University of Colorado Colorado Springs (UCCS), Colorado Springs, 
      Colorado, United States.
AD  - William J. Hybl Sports Medicine and Performance Center, Colorado Springs, 
      Colorado, United States.
FAU - Kirby, Brett S
AU  - Kirby BS
AUID- ORCID: 0000-0002-2033-5970
AD  - Nike Sport Research Lab, Nike, Inc., Beaverton, Oregon, United States.
FAU - Jacobs, Robert A
AU  - Jacobs RA
AUID- ORCID: 0000-0003-0180-8266
AD  - Department of Human Physiology & Nutrition, College of Nursing and Health 
      Sciences, University of Colorado Colorado Springs (UCCS), Colorado Springs, 
      Colorado, United States.
AD  - William J. Hybl Sports Medicine and Performance Center, Colorado Springs, 
      Colorado, United States.
LA  - eng
PT  - Journal Article
DEP - 20231207
PL  - United States
TA  - J Appl Physiol (1985)
JT  - Journal of applied physiology (Bethesda, Md. : 1985)
JID - 8502536
RN  - 9005-79-2 (Glycogen)
SB  - IM
MH  - Humans
MH  - Male
MH  - Female
MH  - *Marathon Running
MH  - Nutritional Status
MH  - *Running/physiology
MH  - Exercise
MH  - Glycogen
MH  - Physical Endurance/physiology
OTO - NOTNLM
OT  - carbohydrate
OT  - glycogen
OT  - metabolism
OT  - mitochondria
OT  - skeletal muscle
EDAT- 2023/12/07 06:42
MHDA- 2024/01/15 12:42
CRDT- 2023/12/07 04:19
PHST- 2024/01/15 12:42 [medline]
PHST- 2023/12/07 06:42 [pubmed]
PHST- 2023/12/07 04:19 [entrez]
AID - 10.1152/japplphysiol.00521.2023 [doi]
PST - ppublish
SO  - J Appl Physiol (1985). 2024 Jan 1;136(1):158-176. doi: 
      10.1152/japplphysiol.00521.2023. Epub 2023 Dec 7.