{"title":"Effects of variable resistance training with different load ratios on lower-limb strength and power in male college students","authors":"Changbo Pan , Wei Li , Yuying Su , Yu Shi","doi":"10.1016/j.jesf.2025.04.001","DOIUrl":null,"url":null,"abstract":"<div><h3>Objective</h3><div>The optimum relationship combination of variable to constant resistance within variable resistance training (VRT) for enhancing lower-limb strength and power remains unclear. This study aimed to investigate how different ratios of variable to constant resistance in VRT affect lower-limb strength and power.</div></div><div><h3>Methods</h3><div>Forty-five male college students (age: 21.65 ± 2.20 years; height: 179.65 ± 4.98 cm; body mass: 77.21 ± 6.77 kg; resistance training experience: 3.00 ± 0.96 years) were randomly assigned to three groups: 20 % VRT (n = 15), 35 % VRT (n = 15), and constant resistance training (CRT, n = 15). All groups trained squats twice weekly for 6 weeks at 80 % 1RM total load (20 % VRT: 20 % variable resistance combined 80 % constant resistance; 35 % VRT: 35 % variable resistance combined 65 % constant resistance; CRT: 100 % constant resistance). Pre- and post-experiment tests included squat 1RM, countermovement jump (CMJ), squat jump (SJ), standing broad jump (SBJ), 20-m sprint, and rectus femoris cross-sectional area (RFCSA). A mixed-design ANOVA (group × time) was used for data analysis.</div></div><div><h3>Results</h3><div>The 20 % VRT group surpassed CRT in maximal strength cross-sectionally (F = 3.565, <em>p</em> = 0.037) but not longitudinally (<em>p</em> = 0.079). All groups improved strength over time (<em>p</em> < 0.001; Cohen's <em>d</em> = 0.87–0.94). A significant interaction (F = 3.407, <em>p</em> = 0.043) indicated SJ improvement for 35 % VRT vs. CRT (<em>p</em> < 0.05, Cohen's <em>d</em> = 0.43), with no CMJ, SBJ, sprint, or RFCSA differences (<em>p</em> > 0.05).</div></div><div><h3>Conclusion</h3><div>VRT and CRT yield equivalent long-term strength gains. Different combinations of variable to constant resistance ratios in VRT (20 % and 35 %) led to distinct task-specific adaptations in lower-limb performance. Practitioners should prioritize 35 % VRT for static explosive tasks, use 20 % VRT as a supplementary strength tool.</div></div>","PeriodicalId":15793,"journal":{"name":"Journal of Exercise Science & Fitness","volume":"23 3","pages":"Pages 181-189"},"PeriodicalIF":2.4000,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Exercise Science & Fitness","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1728869X25000255","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"SPORT SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Objective
The optimum relationship combination of variable to constant resistance within variable resistance training (VRT) for enhancing lower-limb strength and power remains unclear. This study aimed to investigate how different ratios of variable to constant resistance in VRT affect lower-limb strength and power.
Methods
Forty-five male college students (age: 21.65 ± 2.20 years; height: 179.65 ± 4.98 cm; body mass: 77.21 ± 6.77 kg; resistance training experience: 3.00 ± 0.96 years) were randomly assigned to three groups: 20 % VRT (n = 15), 35 % VRT (n = 15), and constant resistance training (CRT, n = 15). All groups trained squats twice weekly for 6 weeks at 80 % 1RM total load (20 % VRT: 20 % variable resistance combined 80 % constant resistance; 35 % VRT: 35 % variable resistance combined 65 % constant resistance; CRT: 100 % constant resistance). Pre- and post-experiment tests included squat 1RM, countermovement jump (CMJ), squat jump (SJ), standing broad jump (SBJ), 20-m sprint, and rectus femoris cross-sectional area (RFCSA). A mixed-design ANOVA (group × time) was used for data analysis.
Results
The 20 % VRT group surpassed CRT in maximal strength cross-sectionally (F = 3.565, p = 0.037) but not longitudinally (p = 0.079). All groups improved strength over time (p < 0.001; Cohen's d = 0.87–0.94). A significant interaction (F = 3.407, p = 0.043) indicated SJ improvement for 35 % VRT vs. CRT (p < 0.05, Cohen's d = 0.43), with no CMJ, SBJ, sprint, or RFCSA differences (p > 0.05).
Conclusion
VRT and CRT yield equivalent long-term strength gains. Different combinations of variable to constant resistance ratios in VRT (20 % and 35 %) led to distinct task-specific adaptations in lower-limb performance. Practitioners should prioritize 35 % VRT for static explosive tasks, use 20 % VRT as a supplementary strength tool.
期刊介绍:
The Journal of Exercise Science and Fitness is the official peer-reviewed journal of The Society of Chinese Scholars on Exercise Physiology and Fitness (SCSEPF), the Physical Fitness Association of Hong Kong, China (HKPFA), and the Hong Kong Association of Sports Medicine and Sports Science (HKASMSS). It is published twice a year, in June and December, by Elsevier.
The Journal accepts original investigations, comprehensive reviews, case studies and short communications on current topics in exercise science, physical fitness and physical education.