The performance effect of scheduled carbohydrate and caffeine intake during simulated team sport match-play

The aim of the current investigation was to identify the effects of scheduled carbohydrate (CHO) and caffeine (CAF) supplementation on simulated team sport match-play performance. Ten male hurling players completed three hurling match-play simulation protocols (HSP) performed 7 days apart in a double-blind, randomized design. Supplementation included CHO, CHO + CAF, and placebo (PLA). In a randomized order, participants ingested either a 6% CHO solution, a PLA solution of similar taste, or a combined intake of 6% CHO solution + 200 mg CAF capsule. At specific time points (Pre-0 min; half time (HT)-30 min; full time (FT)-60 min), participants completed a repeated sprint protocol (RAST; 12 × 20 m). Physiological [% maximal oxygen uptake (%VO_2max), % mean oxygen uptake (%VO_2mean), % maximal heart rate (%HR_max), % mean heart rate (%HR_mean), respiratory exchange ratio (RER), and blood lactate (BLa)] and performance [(best sprint time (RSA_best), mean sprint time (RSA_mean), and rate of perceived exertion (RPE)] variables were monitored throughout each simulation. Non-significant differences were observed between supplement trials (CHO, CHO + CAF, and PLA) for BLa (η² = 0.001, small), %VO_2max (η² = 0.001, small), %VO_2mean (η² = 0.004, small), %HR_max (η² = 0.007, small), %HR_mean (η² = 0.018, small), RER (η² = 0.007, small), RPE (η² = 0.007, small), and RSA_best (η² = 0.050, small). RSA_mean performance significantly improved in CHO + CAF trials compared to PLA, with sprint times significantly improved from Pre to FT also (η² = 0.135, medium). A significant difference was observed in BLa between time points (Pre, HT, and FT) (η² = 0.884, large) in % HRmax (η² = 0.202, medium), %HR_mean (η² = 0.477, large), and RER (η² = 0.554, large) across halves and in RPE across time points (η² = 0.670, large). Our data provide novel data regarding the effects of CHO and CAF supplementation on team sport performance, with co-ingestion of CHO + CAF reducing the decrement in repeated sprint performance compared to PLA.