Effects of Horizontal and Incline Bench Press on Neuromuscular Adaptations in Untrained Young Men

International Journal of Exercise Science 13(6): 859-872, 2020. The aim of the current study was to investigate the effects of horizontal and incline bench press as well as the combination of both exercises on neuromuscular adaptation in untrained young men. Forty-seven untrained men were randomly assigned to one of the three groups: 1) a horizontal bench press group (n= 15), 2) an incline bench press group (n= 15), and 3) a combination (horizontal + incline) group (n= 17). Training was conducted once a week for eight weeks, with equalized number of sets among groups. Muscle thickness, isometric strength and electromyography (EMG) amplitude of the pectoralis major were measured one week before and after the training period. There was no difference between groups for the change in horizontal bench press isometric strength (~ 10 kg increase, p=0.776) or incline bench press isometric strength (~ 11 kg increase, p=0.333). Changes in muscle thickness differed only in one of the three sites. The changes in the second intercostal space of the pectoralis major was greatest in the incline pressure group compared with the horizontal [mean difference (95% CI) of 0.62 (0.23, 1.0) cm, p=0.003] and combination groups [mean difference (95% CI) of 0.50 (0.14, 0.86) cm, p=0.008]. The change in EMG amplitude following training differed between groups in only one out of the four sites. The present results indicate that strength and conditioning professionals might consider that horizontal and incline bench press exercises, or a combination of both exercises can render similar change in general strength

Effects of Detraining on Muscle Strength and Hypertrophy Induced by Resistance Training: A Systematic Review

A detraining period after resistance training causes a significant decrease in trained-induced muscular adaptations. However, it is unclear how long muscle strength and hypertrophy gains last after different detraining periods. Thus, the present systematic review with meta-analysis aimed to evaluate the chronic effects of detraining on muscle strength and hypertrophy induced by resistance training. Searches were conducted on PubMed, Scopus, EBSCO, CINAHL, CENTRAL, and Web of Science. The difference in means and pooled standard deviations of outcomes were converted into Hedges’ g effect sizes (g). Twenty randomized and non-randomized trials (high and moderate risks of bias, respectively, and fair quality) were included for qualitative analysis of muscle strength and hypertrophy, while only two studies were included in the meta-analysis for maximum muscle strength. The resistance training group presented a significant increase in one-repetition maximum (1RM) chest press (g: 4.43 [3.65; 5.22], p < 0.001) and 1RM leg press strength (g: 4.47 [2.12; 6.82], p < 0.001) after training. The strength gains observed in the resistance training group were also maintained after 16–24 weeks of detraining (g: 1.99 [0.62; 3.36], p = 0.004; and g: 3.16 [0.82; 5.50], p = 0.008; respectively), when compared to the non-exercise control group. However, 1RM chest press and leg press strength level was similar between groups after 32 (g: 1.81 [−0.59; 4.21], p = 0.139; and g: 2.34 [−0.48; 5.16], p = 0.104; respectively) and 48 weeks of detraining (g: 1.01 [−0.76; 2.79], p = 0.263; and g: 1.16 [−1.09; 3.42], p = 0.311; respectively). There was not enough data to conduct a meta-analysis on muscular hypertrophy. In conclusion, the present systematic review and meta-analysis demonstrated that, when taking random error into account, there is no sufficient high-quality evidence to make any unbiased claim about how long changes in muscle strength induced by RT last after a DT period. Moreover, the effect of different DT periods on muscle hypertrophy induced by RT remains unknown since there was not enough data to conduct a meta-analysis with this variable