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We investigated the effect of ischemic preconditioning (IPC) with and without caffeine supplementation on mean power output (MPO) during a 4‐min cycling time‐trial (TT). In a double‐blinded, randomized, crossover‐design, 11 trained men performed a TT on 4 days separated by ∼1 week. One hour before TT, participants ingested either caffeine (3 mg kg bw−1) or placebo pills, after which femoral blood‐flow was either restricted with occlusion cuffs inflated to ∼180 mmHg (IPC), or sham‐restricted (0–10 mmHg; Sham) during 3 × 2‐min low‐intensity cycling (10% of incremental peak power output). Then, participants performed a standardized warm‐up followed by the TT. Plasma lactate and K+ concentrations and ratings of perceived exertion (RPE) were measured throughout trials. TT MPO was 382 ± 17 W in Placebo + Sham and not different from Placebo + IPC (−1 W; 95% CI: −9 to 7; p = 0.848; d: 0.06), whereas MPO was higher with Caffeine + Sham (+6W; 95% CI: −2 to 14; p = 0.115; d: 0.49) and Caffeine + IPC (+8 W; 95% CI: 2–13; p = 0.019; d: 0.79) versus Placebo + Sham. MPO differences were attributed to caffeine (caffeine main‐effect: +7 W; 95% CI: 2–13; p = 0.015; d: 0.54. IPC main‐effect: 0 W; 95% CI: −6 to 7; p = 0.891; d: 0.03; caffeine × IPC interaction‐effect: p = 0.580; d: 0.17). TT RPE and plasma variables were not different between treatments. In conlcusion, IPC with co‐ingestion of placebo does not improve short‐term high‐intensity performance in trained men versus a double‐placebo control (Placebo + Sham) and does not additively enhance performance with caffeine. These data do not support IPC as a useful strategy for athletes prior to competition but confirms caffeine's performance‐enhancing effect. Highlights: Active ischemic preconditioning (IPC) prior to exercise has been proposed as a strategy to enhance short‐term exercise performance.However, the effect of combined IPC and caffeine ingestion on short‐term high‐intensity exercise performance in trained individuals remains unclear.Active IPC with co‐ingestion of placebo pills did not improve short‐term high‐intensity exercise performance in trained men and its use cannot be recommended over caffeine to improve subsequent short‐term maximal performanceIngestion of caffeine (3 mg kg bw−1) prior to short‐term high‐intensity exercise is an effective ergogenic strategy which athletes may benefit from. [ABSTRACT FROM AUTHOR]

Purpose: We investigated whether 4 weeks of intensified training consisting of speed endurance training (SET) enhanced high-intensity exercise performance in youth national-team ice hockey players. Methods: Utilizing a randomized crossover design, we subjected 17 players to 4 weeks of SET, comprising 6 to 10 × 20 seconds at maximal effort (>95% maximum ice skating speed) with 120-second recovery performed 3 times weekly, or maintenance of regular training (control period). Before and after each period, players completed ice-hockey-specific tests on ice, including a Yo-Yo Intermittent Recovery Level 1 test, a 30-m sprint test, and an agility test. On a separate day, players were assessed for body composition with dual-energy X-ray absorptiometry and performed countermovement jump, maximal voluntary isometric knee extensor contraction, a 15-second maximal sprint test, and a submaximal and incremental test on a bike ergometer in which pulmonary oxygen consumption was determined. Results: Yo-Yo Intermittent Recovery Level 1 test performance increased (P <.001) by 14% (95% CI, 201–496 m) during the SET period. Maximal pulmonary oxygen consumption (P <.05) and time to exhaustion (P <.05) were 4.8% and 6.5% higher, respectively, after the SET period than before. Fat-free mass increased (P <.01) during the SET period by 1.7 kg (95% CI, 1.0–2.5), whereas fat mass remained unchanged. These effects were superior to the control period. Conclusions: These findings underpin the effectiveness of SET for improving on-ice high-intensity performance and highlight that elite ice hockey players can benefit from implementing SET. [ABSTRACT FROM AUTHOR]