Effects of Stair-Climbing Exercise Snacks with Blood Flow Restriction on Fitness in Sedentary University Students: A Pilot Randomized Controlled Trial

Time-efficient strategies are needed to enhance physical fitness in sedentary university students. This pilot study examined the preliminary effects of maximal-effort stair-climbing exercise snacks performed alone (ESA) or combined with practical blood flow restriction (ES + BFR). Twenty-three sedentary male university students were included in the per-protocol analysis (ESA, n = 7; ES + BFR, n = 8; control, n = 8). Over 4 weeks, both intervention groups completed 48 supervised sessions, each consisting of three 20 s maximal stair climbs separated by 2 min rest. Assessed outcomes were forced vital capacity (FVC), 50 m sprint time, 1000 m run time, standing long jump (SLJ), sit-and-reach flexibility, and body mass index (BMI). Group × Time interactions were tested using mixed-model ANOVA. Significant interactions emerged for all metrics (p ≤ 0.01, partial η2 = 0.35–0.70), except BMI. Both interventions significantly improved FVC, flexibility, 1000 m run and 50 m sprint performance (p < 0.05; absolute Cohen’s d range = 1.01–2.68). Although no significant between-group differences were observed, ES + BFR produced larger within-group effect sizes than ESA for 1000 m run time (d = −2.14 vs. −1.66) and 50 m sprint time (d = −2.21 vs. −1.89). Only ES + BFR significantly increased SLJ (p < 0.05), whereas the control group exhibited a significant decline (p < 0.05). BMI remained unchanged. The 4-week stair-climbing exercise snack protocol is feasible and may improve pulmonary function, endurance, speed, and flexibility in sedentary male students. Adding practical BFR shows promising numerical benefits for sprint, power, and endurance performance, but these exploratory findings require confirmation in larger trials.