title: Changes in aerobic capacity and glycaemic control in response to reduced-exertion high-intensity interval training (REHIT) are not different between sedentary men and women.
abstract: Previously it has been reported that reduced-exertion high-intensity interval training (REHIT; total training time of 3 × 10 min per week) improves maximal aerobic capacity in both sedentary men and women, but improves insulin sensitivity in men only. The aim of the present study was to determine whether there is a true sex difference in response to REHIT, or that these findings can be explained by the large interindividual variability in response inherent to all exercise training. Thirty-five sedentary participants (18 women; mean ± SD age for men and women, respectively: age, 33 ± 9 and 36 ± 9 years; body mass index, 25.1 ± 2.1 and 24.1 ± 3.5 kg·m-2; maximal aerobic capacity, 38.6 ± 8.3 and 31.6 ± 4.6 mL·kg-1·min-1) completed a 6-week REHIT programme consisting of eighteen 10-min unloaded cycling sessions with 1 (first session) or 2 (all other sessions) "all-out" 10-20-s sprints against a resistance of 5% of body mass. Maximal aerobic capacity and oral glucose tolerance test-derived insulin sensitivity were determined before and after training. REHIT was associated with an increase in maximal aerobic capacity (2.54 ± 0.65 vs. 2.78 ± 0.68 L·min-1, main effect of time: p < 0.01), a trend toward reduced plasma insulin area-under-the-curve (AUC; 6.7 ± 4.8 vs. 6.1 ± 4.0 IU·min-1·mL-1, p = 0.096), but no significant change in plasma glucose AUC or the Cederholm index of insulin sensitivity. Substantial interindividual variability in response to REHIT was observed for all variables, but there was no significant effect of sex. In conclusion, REHIT improves the key health marker of aerobic capacity within a minimal total training time-commitment. There is large interindividual variability in responses to REHIT, but sex differences in the responses are not apparent.
authors.affiliation: a Department for Health, University of Bath, Bath BA2 7AY, UK.|b School of Sport, Ulster University, Northern Ireland, UK.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Metcalfe
authors.affiliation: c Department of Clinical Sciences, Intervention and Technology (CLINTEC), Karolinska Institutet, Karolinska University Hospital, Stockholm 141 52, Sweden.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Tardif
authors.affiliation: a Department for Health, University of Bath, Bath BA2 7AY, UK.
authors.forename: Dylan
authors.initials: D
authors.lastname: Thompson
authors.affiliation: a Department for Health, University of Bath, Bath BA2 7AY, UK.
authors.forename: Niels B J
authors.initials: NB
authors.lastname: Vollaard
mesh_terms: D000328:Adult; D001642:Bicycling; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000517:prevention & control; D015331:Cohort Studies; D017079:Exercise Tolerance; D005260:Female; D044882:Glucose Metabolism Disorders / Q000453:epidemiology / Q000517:prevention & control; D005951:Glucose Tolerance Test; D000072696:High-Intensity Interval Training; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D005082:Physical Exertion; D010809:Physical Fitness; D015203:Reproducibility of Results; D012307:Risk Factors; D057185:Sedentary Behavior; D012727:Sex Characteristics; D006113:United Kingdom / Q000453:epidemiology; D055815:Young Adult
keywords: HIT; V̇O2max; différences liées au sexe; insulin sensitivity; sensibilité à l’insuline; sex differences