High intensity interval exercise is an effective alternative to moderate intensity exercise for improving glucose tolerance and insulin sensitivity in adolescent boys. Issue 6 (November 2015)

• Record Type: Journal Article
• Authors: Cockcroft, Emma J.; Williams, Craig A.; Tomlinson, Owen W.; Vlachopoulos, Dimitris; Jackman, Sarah R.; Armstrong, Neil; Barker, Alan R.
• Is Part Of: Journal of science and medicine in sport. Volume 18:Issue 6(2015:Nov.)
• Page Start: 720
• Page End: 724
• Publication Date: 2015-11
• Subjects: Sports sciences -- Periodicals; Sports medicine -- Periodicals; Exercise -- Physiological aspects -- Periodicals; Sports -- physiology -- Periodicals; Sports Medicine -- Periodicals; Sportgeneeskunde; 617.102705
• DOI: 10.1016/j.jsams.2014.10.001
• Languages: English
• ISSNs: 1440-2440

Abstract

<abstract abstract-type="author" id="abs0005"> <title id="sect0005">Abstract</title> <sec> <title id="sect0010">Objectives</title> <p id="spar0005">High-intensity interval exercise (HIIE) may offer a time efficient means to improve health outcomes compared to moderate-intensity exercise (MIE). This study examined the acute effect of HIIE compared to a work-matched bout of MIE on glucose tolerance, insulin sensitivity (IS), resting fat oxidation and exercise enjoyment in adolescent boys.</p> </sec> <sec> <title id="sect0011">Design</title> <p id="spar0006">Within-measures design with counterbalanced experimental conditions.</p> </sec> <sec> <title id="sect0015">Methods</title> <p id="spar0010">Nine boys (14.2 ± 0.4 years) completed three conditions on separate days in a counterbalanced order: (1) HIIE; (2) work matched MIE, both on a cycle ergometer; and (3) rest (CON). An oral glucose tolerance test (OGTT) was performed after exercise or rest and the area under curve (AUC) responses for plasma [glucose] and [insulin] were calculated, and IS estimated (Cederholm index). Energy expenditure and fat oxidation were measured following the OGTT using indirect calorimetry. Exercise enjoyment was assessed using the Physical Activity Enjoyment Scale.</p> </sec> <sec> <title id="sect0020">Results</title> <p id="spar0015">The incremental AUC (iAUC) for plasma [glucose] was reduced following both MIE (−23.9%, <italic>P</italic> = 0.013, effect size [ES] = −0.64) and HIIE (−28.9%, <italic>P</italic> = 0.008, ES = −0.84) compared to CON. The iAUC for plasma [insulin] was lower for HIIE (−24.2%, <italic>P</italic> = 0.021, ES = −0.71) and MIE (−29.1%, <italic>P</italic> = 0.012, ES = −0.79) compared to CON. IS increased by 11.2% after HIIE (<italic>P</italic> = 0.03, ES = 0.76) and 8.4% after MIE (<italic>P</italic> = 0.10, ES = 0.58). There was a trend for an increase in fat oxidation following HIIE (<italic>P</italic> = 0.097, ES = 0.70). Both HIIE and MIE were rated as equally enjoyable (<italic>P</italic> > 0.05, ES < 0.01).</p> </sec> <sec> <title id="sect0025">Conclusion</title> <p id="spar0020">A single bout of time efficient HIIE is an effective alternative to MIE for improving glucose tolerance and IS in adolescent boys immediately after exercise.</p> </sec> </abstract>