Compatibility of Concurrent Aerobic and Strength Training for Skeletal Muscle Size and Function: An Updated Systematic Review and Meta-Analysis

Abstract

Background Both athletes and recreational exercisers often perform relatively high volumes of aerobic and strength training simultaneously. However, the compatibility of these two distinct training modes remains unclear. Objective This systematic review assessed the compatibility of concurrent aerobic and strength training compared with strength training alone, in terms of adaptations in muscle function (maximal and explosive strength) and muscle mass. Subgroup analyses were conducted to examine the influence of training modality, training type, exercise order, training frequency, age, and training status. Methods A systematic literature search was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. PubMed/MEDLINE, ISI Web of Science, Embase, CINAHL, SPORTDiscus, and Scopus were systematically searched (12 August 2020, updated on 15 March 2021). Eligibility criteria were as follows. Population: healthy adults of any sex and age; Intervention: supervised concurrent aerobic and strength training for at least 4 weeks; Comparison: identical strength training prescription, with no aerobic training; Outcome: maximal strength, explosive strength, and muscle hypertrophy. Results A total of 43 studies were included. The estimated standardised mean differences (SMD) based on the random-effects model were − 0.06 (95% confidence interval [CI] − 0.20 to 0.09; p = 0.446), − 0.28 (95% CI − 0.48 to − 0.08; p = 0.007), and − 0.01 (95% CI − 0.16 to 0.18; p = 0.919) for maximal strength, explosive strength, and muscle hypertrophy, respectively. Attenuation of explosive strength was more pronounced when concurrent training was performed within the same session (p = 0.043) than when sessions were separated by at least 3 h (p > 0.05). No significant effects were found for the other moderators, i.e. type of aerobic training (cycling vs. running), frequency of concurrent training (> 5 vs. < 5 weekly sessions), training status (untrained vs. active), and mean age (< 40 vs. > 40 years). Conclusion Concurrent aerobic and strength training does not compromise muscle hypertrophy and maximal strength development. However, explosive strength gains may be attenuated, especially when aerobic and strength training are performed in the same session. These results appeared to be independent of the type of aerobic training, frequency of concurrent training, training status, and age. PROSPERO: CRD42020203777.

How Do Master Weightlifters Train? A Transnational Study of Weightlifting Training Practices and Concurrent Training

“…Trained individuals may also experience more negative effects on strength gains with concurrent training compared to untrained individuals [ 34 ]. However, data presented in a recent literature review on concurrent endurance and strength training suggest this approach to training does not compromise muscle hypertrophy and maximal strength development irrespective of frequency, age (less than 40 years versus older), and untrained or trained status [ 35 ]. The conflicting messaging about the interfering effects of concurrent training is likely attributed to differences in the experimental settings and study participants.…”

“…The conflicting messaging about the interfering effects of concurrent training is likely attributed to differences in the experimental settings and study participants. Both endurance and strength exercises can be incorporated in training programs with a low risk of interference effects if one considers volume, intensity, and frequency of each exercise [ 35 , 36 ], but for competitive weightlifters, it is important to consider that concurrent training may compromise explosive power as measured by jump height and other rapid force production, and thus they may benefit from separating endurance and strength training to minimize the potential interference effects [ 35 , 37 , 38 ].…”

“…Muscle physiology changes in the aging athlete and exercise regimens and nutrition are modifiable contributing factors [ 51 ]. Some practical aspects to consider for the training of older weightlifters are: In our study we found that older female weightlifters may have capacity for a higher training frequency than older males, Concurrent aerobic physical activities could be added to the training program to reach WHO guidelines to help maintain health and fitness at older ages without it being detrimental to the strength gains [ 35 ], Engagement in concurrent training and other sports needs to be considered to ensure proper recovery and avoid overtraining, More emphasis could be put on nutrition. Most females in this study were aware of its benefits on weightlifting training and recovery, but that awareness was lacking in some older male weightlifters.…”

“…Concurrent aerobic physical activities could be added to the training program to reach WHO guidelines to help maintain health and fitness at older ages without it being detrimental to the strength gains [ 35 ],…”

Effects of Cycling Intensity on Acute Signaling Adaptations to 8-weeks Concurrent Training in Trained Cyclists

“…Interestingly, these authors assessed numerous aspects of CMJ performance, with the only significant improvement reported for peak velocity in the moderate-intensity group. Power is a critical parameter in the context of concurrent training, as it is the only outcome to detrimentally change relative to resistance training in isolation, according to a recent meta-analysis ( Schumann et al, 2021 ). Whilst it is positive that both concurrent training programmes from this study resulted in improved CMJ performance, it is not possible to place this finding in the context of the interference effect, given the design used in this work.…”