TY - JOUR

T1 - Peak Fat Oxidation is Not Independently Related to Ironman Performance in Women

AU - Vest, Stine Dahl

AU - Frandsen, Jacob

AU - Larsen, Steen

AU - Dela, Flemming

AU - Helge, Jørn Wulff

N1 - © Georg Thieme Verlag KG Stuttgart · New York.

PY - 2018

Y1 - 2018

N2 - The aim of the present study was to investigate if peak fat oxidation rate (PFO) is related to Ironman performance in female athletes. Thirty-six female Ironman athletes (age: 34±1 yrs, [21-45 yrs.] SEM [Range]) with a BMI of 22.1±2.0 kg/m 2 [18.8-28.4 kg/m 2 ], a body fat percentage of 24.8±1.0% [9.0-37.0%] and a VO 2 peak of 53.0±1.3 ml/min/kg [36.5-70.5 ml/min/kg] were tested in the laboratory prior to the Ironman Copenhagen 2017. Race time ranged from 9:17:07 to 15:23:48 with mean race time being 11:57:26 h:min:s (717 min). By simple linear regression analyses we found associations between race time and P FO (r 2 =0.22, p<0.005), VO 2 peak (r 2 =0.65, p<0.0001) and the relative exercise intensity eliciting PFO (Fatmax) (r 2 =0.35, p=0.0001). Furthermore, associations were found between race time and body fat percentage (r 2 =0.44, p<0.0001) and age (r 2 =0.16, p<0.05). By means of multiple regression analysis, VO 2 peak was the only statistically significant variable explaining 64% of the variation in race time (adj. r 2 =0.64, p<0.005). In conclusion, these results demonstrate that PFO is not independently related to Ironman performance in a heterogeneous group of female athletes. Interestingly, VO 2 peak alone was able to predict 64% of the variation in Ironman race times.

AB - The aim of the present study was to investigate if peak fat oxidation rate (PFO) is related to Ironman performance in female athletes. Thirty-six female Ironman athletes (age: 34±1 yrs, [21-45 yrs.] SEM [Range]) with a BMI of 22.1±2.0 kg/m 2 [18.8-28.4 kg/m 2 ], a body fat percentage of 24.8±1.0% [9.0-37.0%] and a VO 2 peak of 53.0±1.3 ml/min/kg [36.5-70.5 ml/min/kg] were tested in the laboratory prior to the Ironman Copenhagen 2017. Race time ranged from 9:17:07 to 15:23:48 with mean race time being 11:57:26 h:min:s (717 min). By simple linear regression analyses we found associations between race time and P FO (r 2 =0.22, p<0.005), VO 2 peak (r 2 =0.65, p<0.0001) and the relative exercise intensity eliciting PFO (Fatmax) (r 2 =0.35, p=0.0001). Furthermore, associations were found between race time and body fat percentage (r 2 =0.44, p<0.0001) and age (r 2 =0.16, p<0.05). By means of multiple regression analysis, VO 2 peak was the only statistically significant variable explaining 64% of the variation in race time (adj. r 2 =0.64, p<0.005). In conclusion, these results demonstrate that PFO is not independently related to Ironman performance in a heterogeneous group of female athletes. Interestingly, VO 2 peak alone was able to predict 64% of the variation in Ironman race times.

KW - Adipose Tissue/metabolism

KW - Adult

KW - Athletic Performance/physiology

KW - Bicycling

KW - Calorimetry, Indirect

KW - Fatty Acids/blood

KW - Female

KW - Glycerol/blood

KW - Humans

KW - Middle Aged

KW - Oxidation-Reduction

KW - Oxygen Consumption

KW - Regression Analysis

KW - Running

KW - Swimming

KW - Young Adult

UR - http://www.scopus.com/inward/record.url?scp=85056213615&partnerID=8YFLogxK

U2 - 10.1055/a-0660-0031

DO - 10.1055/a-0660-0031

M3 - Journal article

C2 - 30227458

VL - 39

SP - 916

EP - 923

JO - International Journal of Sports Medicine

JF - International Journal of Sports Medicine

SN - 0172-4622

IS - 12

ER -