Physiological Interpretation of the Slope during an Isokinetic Fatigue Test.
To assess the relationship between selected measures (the slope and average performance) obtained during a high intensity isokinetic fatigue test of the knee (FAT) and relevant measures of anaerobic and aerobic capacities. 20 well-trained cyclists performed 3 randomly ordered sessions involving a FAT consisting in 30 reciprocal maximal concentric contractions of knee flexors and extensors at 180°.s(-1), a maximal continuous graded exercise test (GXT), and a Wingate anaerobic test (WAnT). The slope calculated from peak torque (PT) and total work (TW) of knee extensors was highly associated to maximal PT (r=-0.86) and maximal TW (r=-0.87) measured during FAT, and moderately associated to peak power output measured during the WAnT (r=-0.64 to -0.71). Average PT and average TW were highly associated to maximal PT (r=0.93) and maximal TW (r=0.96), to mean power output measured during WAnT (r=0.83-0.90) and moderately associated to maximal oxygen uptake (0.58-0.67). In conclusion, the slope is mainly determined by maximal anaerobic power, while average performance is a composite measure depending on both aerobic and anaerobic energy systems according to proportions that are determined by the duration of the test.
Université de Poitiers, Faculté des sciences du sport, Poitiers, France.
L
L
Bosquet
Kinesiology, University of Montreal, Montreal, Canada.
K
K
Gouadec
Kinesiology, University of Montreal, Montreal, Canada.
N
N
Berryman
Physical Medicine and Rehabilitation, University of Montreal, Montreal, Canada.
C
C
Duclos
Medicine, Université de Dijon, Dijon, France.
V
V
Gremeaux
Physical Medicine and Rehabilitation, University of Liege, LIEGE, Belgium.
J-L
JL
Croisier
D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology*; D001642:Bicycling / Q000502:physiology; D001696:Biomechanical Phenomena; D005080:Exercise Test; D006801:Humans; D007717:Knee / Q000502:physiology*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018763:Muscle Fatigue / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology; D011897:Random Allocation; D019415:Torque