Development of Maximal Dynamic Strength During Concurrent Resistance and Endurance Training in Untrained, Moderately Trained, and Trained Individuals: A Systematic Review and Meta-analysis

Abstract

Background The effect of concurrent training on the development of maximal strength is unclear, especially in individuals with different training statuses. Objective The aim of this systematic review and meta-analysis study was to compare the effect of concurrent resistance and endurance training with that of resistance training only on the development of maximal dynamic strength in untrained, moderately trained, and trained individuals. Methods On the basis of the predetermined criteria, 27 studies that compared effects between concurrent and resistance training only on lower-body 1-repetition maximum (1RM) strength were included. The effect size (ES), calculated as the standardised difference in mean, was extracted from each study, pooled, and analysed with a random-effects model. Results The 1RM for leg press and squat exercises was negatively affected by concurrent training in trained individuals (ES = – 0.35, p < 0.01), but not in moderately trained ( – 0.20, p = 0.08) or untrained individuals (ES = 0.03, p = 0.87) as compared to resistance training only. A subgroup analysis revealed that the negative effect observed in trained individuals occurred only when resistance and endurance training were conducted within the same training session (ES same session = – 0.66, p < 0.01 vs. ES different sessions = – 0.10, p = 0.55). Conclusion This study demonstrated the novel and quantifiable effects of training status on lower-body strength development and shows that the addition of endurance training to a resistance training programme may have a negative impact on lower-body strength development in trained, but not in moderately trained or untrained individuals. This impairment seems to be more pronounced when training is performed within the same session than in different sessions. Trained individuals should therefore consider separating endurance from resistance training during periods where the development of dynamic maximal strength is prioritised.

Compatibility of concurrent aerobic and strength training for skeletal muscle size and function: an updated systematic review and meta-analysis

“…The moderators, including training volume, type of exercise, age, and training status, neither significantly influenced adaptations in maximal and explosive strength, nor muscle hypertrophy. Thus, our results differ from the recently published meta-analysis focusing solely on the effect of training status on maximal strength during concurrent training 16 . In that study the 1RM for leg press and squat exercise was negatively affected by concurrent training in trained individuals but not in moderately trained or untrained individuals compared with strength training alone.…”

“…However, due to lack of consistent reporting we decided not to group active participants into moderately or well-trained athletes and this may have diluted possible significant effects. Furthermore, albeit the exact calculations were not published by Petré et al 2021 16 , their analysis appears to differ from our approach. Apart from the fewer number of studies included (27 vs. 37 studies), studies consisting of multiple intervention groups with only one comparator were included multiple times within the same analysis, potentially inflating power 74 .…”

“…Apart from the fewer number of studies included (27 vs. 37 studies), studies consisting of multiple intervention groups with only one comparator were included multiple times within the same analysis, potentially inflating power 74 . However, although the results did not reach statistical significance, our subgroup analysis for training status indicated a similar direction for the SMD in trained compared to untrained participants as reported by Petré et al 16 .…”

“…The first meta-analysis conducted a decade ago by Wilson and colleagues showed that peak power was attenuated with concurrent training compared with strength training alone, while the development of muscle hypertrophy and maximal strength were not compromised 15 . A more recent meta-analysis aimed to compare the effect of concurrent aerobic and strength training with strength training alone on the development of maximal strength in untrained, moderately trained and trained individuals 16 . The results suggested that concurrent training may have a negative impact on lower body strength development in trained, but not in moderately trained or untrained individuals.…”

Skeletal Muscle Quality: A Biomarker for Assessing Physical Performance Capabilities in Young Populations

“…Different training modalities for improving MQ in young, healthy populations. Shown to improve muscle capillarization and cardiorespiratory fitness; significantly decreases adipose tissue, subsequently improving lean mass to adipose ratio and overall tissue quality Can lead to decreased muscle mass; been shown to be less optimal for improving strength and power output compared to HIIT and RET; concurrent training (i.e., simultaneous inclusion of endurance and resistance training) has been shown to lead to impairments in explosive strength of trained musclesPutman et al, 2004;Wilson et al, 2012;Hellsten and Nyberg, 2015;Hughes et al, 2018;Petre et al, 2021 …”