Muscular adaptations in low- versus high-load resistance training: A meta-analysis

There has been much debate as to optimal loading strategies for maximising the adaptive response to resistance exercise. The purpose of this paper therefore was to conduct a meta-analysis of randomised controlled trials to compare the effects of low-load (≤60% 1 repetition maximum [RM]) versus high-load (≥65% 1 RM) training in enhancing post-exercise muscular adaptations. The strength analysis comprised 251 subjects and 32 effect sizes (ESs), nested within 20 treatment groups and 9 studies. The hypertrophy analysis comprised 191 subjects and 34 ESs, nested with 17 treatment groups and 8 studies. There was a trend for strength outcomes to be greater with high loads compared to low loads (difference = 1.07 ± 0.60; CI: ?0.18, 2.32; p = 0.09). The mean ES for low loads was 1.23 ± 0.43 (CI: 0.32, 2.13). The mean ES for high loads was 2.30 ± 0.43 (CI: 1.41, 3.19). There was a trend for hypertrophy outcomes to be greater with high loads compared to low loads (difference = 0.43 ± 0.24; CI: ?0.05, 0.92; p = 0.076). The mean ES for low loads was 0.39 ± 0.17 (CI: 0.05, 0.73). The mean ES for high loads was 0.82 ± 0.17 (CI: 0.49, 1.16). In conclusion, training with loads ≤50% 1 RM was found to promote substantial increases in muscle strength and hypertrophy in untrained individuals, but a trend was noted for superiority of heavy loading with respect to these outcome measures with null findings likely attributed to a relatively small number of studies on the topic.     

水电站的低负荷运行

阐述了水电站低负荷运行对机组气蚀、振动、压力脉动和运行稳定性的影响，并从优化设计和优化运行方式两个方面给出了改善低负荷运行工况的措施。     

蒸汽锅炉低负荷运行对水动力可靠性的影响

本文从水动力可靠性方面对Y-130/39-2型锅炉低负荷运行的安全性进行研究和分析.结果表明:50%负荷以上水循环可靠;40%负荷循环流量有波动,但水循环可靠;30%负荷不宜长期运行;20%负荷不宜运行.