This study was designed to test the reproducibility of muscle oxygenation by NIRS in children during exercise. Twelve healthy non-obese and non-trained children performed one maximal graded test, and four 6-min constant load cycle exercises. Deoxy-hemoglobin (Hb/Mb-H+) data were averaged every 1, 5, 10, 20 and 30s. Hb/Mb-H+ data averaged every 5, 10, 20 and 30s showed good reproducibility. When averaged every second, Hb/Mb-H+ values were reproducible after the first minute of exercise. Based on 1s averaged signal modeling, time period and t values for Hb/Mb-H+ were not reproducible but mean response time values showed an acceptable reproducibility.
Erwan Leclair, Delphine Thevenet, Sophie C. Reguem, Benoit Borel, Georges Baquet, Serge Berthoin, and Patrick Mucci
Erwan Leclair, Benoit Borel, Delphine Thevenet, Georges Baquet, Patrick Mucci, and Serge Berthoin
This study first aimed to compare critical power (CP) and anaerobic work capacity (AWC), to laboratory standard evaluation methods such as maximal oxygen uptake (V̇O2max) and maximal accumulated oxygen deficit (MAOD). Secondly, this study compared child and adult CP and AWC values. Subjects performed a maximal graded test to determine V̇O2max and maximal aerobic power (MAP); and four constant load exercises. In children, CP (W.kg−1) was related to V̇O2max (ml.kg−1.min−1; r = .68; p = .004). AWC (J.kg−1) in children was related to MAOD (r = .58; p = .018). Children presented lower AWC (J.kg−1; p = .001) than adults, but similar CP (%MAP) values. CP (%MAP and W.kg−1) and AWC (J.kg−1) were significantly related to laboratory standard evaluation methods but low correlation indicated that they cannot be used interchangeably. CP (%MAP) was similar in children and adults, but AWC (J.kg−1) was significantly lower in children. These conclusions support existing knowledge related to child-adults characteristics.
Serge Berthoin, Georges Baquet, Fabienne Mantéca, Ghislaine Lensel-Corbeil, and Michel Gerbeaux
A cross-sectional design was used to study the associations among sex, age, maximal aerobic speed (MAS), and running time to exhaustion at 100% of MAS (Tlim). The subjects were 1,448 schoolchildren (685 males and 763 females) ages 6 to 17 years. The MAS of males increased significantly (p < .001) from 6 (9.0 ± 0.8 km · h−1) to 17 years (14.1 ± 1.6 km · h−1). The MAS of females increased significantly (p < .001) from 6 (8.7 ± 0.6 km · h−1) to 12 years (10.7 ± 1.2 km · h−1), then remained relatively constant at approximately 11 km · h−1 between 12 and 17 years. Tlim increased significantly from 6 to 13 years for males and from 6 to 11 years for females, then remained relatively constant around 350 s for both males and females.
Georges Baquet, Gregory Dupont, François-Xavier Gamelin, Julien Aucouturier, and Serge Berthoin
This study aimed to compare the effect of active recovery (AR) versus passive recovery (PR) on time to exhaustion and time spent at high percentages of peak oxygen uptake (
Abd-Elbasset Abaïdia, Julien Lamblin, Barthélémy Delecroix, Cédric Leduc, Alan McCall, Mathieu Nédélec, Brian Dawson, Georges Baquet, and Grégory Dupont
To compare the effects of cold-water immersion (CWI) and whole-body cryotherapy (WBC) on recovery kinetics after exercise-induced muscle damage.
Ten physically active men performed single-leg hamstring eccentric exercise comprising 5 sets of 15 repetitions. Immediately postexercise, subjects were exposed in a randomized crossover design to CWI (10 min at 10°C) or WBC (3 min at –110°C) recovery. Creatine kinase concentrations, knee-flexor eccentric (60°/s) and posterior lower-limb isometric (60°) strength, single-leg and 2-leg countermovement jumps, muscle soreness, and perception of recovery were measured. The tests were performed before and immediately, 24, 48, and 72 h after exercise.
Results showed a very likely moderate effect in favor of CWI for single-leg (effect size [ES] = 0.63; 90% confidence interval [CI] = –0.13 to 1.38) and 2-leg countermovement jump (ES = 0.68; 90% CI = –0.08 to 1.43) 72 h after exercise. Soreness was moderately lower 48 h after exercise after CWI (ES = –0.68; 90% CI = –1.44 to 0.07). Perception of recovery was moderately enhanced 24 h after exercise for CWI (ES = –0.62; 90% CI = –1.38 to 0.13). Trivial and small effects of condition were found for the other outcomes.
CWI was more effective than WBC in accelerating recovery kinetics for countermovement-jump performance at 72 h postexercise. CWI also demonstrated lower soreness and higher perceived recovery levels across 24–48 h postexercise.