The relationship between peak fat oxidation and prolonged double-poling endurance exercise performance

Area of Science:

• Exercise Physiology
• Sports Science
• Metabolic Adaptations

Background:

• Peak fat oxidation rate (PFO) and the exercise intensity at PFO (Fatmax) are established predictors of endurance performance in lower body exercise.
• Their role in predominant upper body exercise, such as cross-country skiing, remains less understood.

Purpose of the Study:

• To investigate the relationship between PFO and Fatmax during upper body exercise (ski-ergometer with double-poling) and long-distance cross-country skiing performance.
• To explore potential differences between recreational and elite skiers.
• To assess the modality specificity of these relationships using a cycle-ergometer test.

Main Methods:

• Forty-three healthy men (35 recreational, 8 elite skiers) underwent a graded exercise test on a ski-ergometer using double-poling (GET-DP) and completed the Vasaloppet race.
• Recreational skiers also performed a graded exercise test on a cycle-ergometer (GET-Cycling).
• Measurements included peak fat oxidation rate (PFO) and the intensity at which it occurred (Fatmax).

Main Results:

• Across all participants, Fatmax was the sole independent predictor of Vasaloppet performance (adj. R² = .36).
• Elite skiers showed a strong association between Fatmax and performance (r² = .54).
• Recreational skiers' performance was linked to double-poling Fatmax (r² = .11) and ski-specific training (r² = .30), but not to PFO or cycling-derived Fatmax.

Conclusions:

• Prolonged endurance performance in upper body exercise is primarily predicted by Fatmax, not PFO.
• Fatmax is a key determinant of performance in elite skiers.
• For recreational skiers, double-poling Fatmax and training background are important performance predictors, suggesting exercise modality specificity in fat oxidation-performance relationships.