The Muscle Mag
After eight weeks of supplementation with 40 grams of whey-based protein in shake form from Fresenius Kabi, combined with an endurance and resistance training exercise routine, there was a significant improvement in leg muscle strength compared to a placebo.
The researchers from Friedrich-Alexander University Erlangen-Nürnberg in Germany stated, “Individuals who combine low-volume endurance and resistance training in the same session may benefit from targeted protein supplementation, especially for maximizing improvements in leg muscle strength.”
Endurance and resistance training
Both aerobic and resistance training are recommended for overall fitness and health improvement, but research suggests that concurrent training, especially when done in the same session, can cause physiological stress and potentially interfere with muscle strength and hypertrophy gains due to competing adaptations. Simultaneous endurance and resistance training may also lead to a reduced capacity to develop muscle strength compared to resistance-only training.
Nutrition strategies are often used to counteract the negative effects of training, with protein being a popular choice known for aiding muscle repair and growth. However, most data is limited to athletes and physically active individuals.
Study details
To address this gap in knowledge, 44 untrained, healthy men and women aged 21 to 33 were recruited to perform two sessions per week of low-volume high-intensity interval training followed by five machine-based resistance training exercises. Half of the participants received 40 grams of whey-based protein, while the other half received an isocaloric placebo after each session.
Both groups saw a significant increase in maximal oxygen consumption (VO2max) and overall fitness scores. Additionally, muscular strength improved in both groups, but the protein group experienced significantly greater gains in leg muscle strength.
The researchers highlighted the potential clinical relevance of even small strength gains, noting that targeted post-exercise protein supplementation can improve adaptations to low-volume concurrent training, particularly leg muscle strength, in untrained healthy individuals.
They hypothesized that the increased muscle protein synthesis response from protein supplementation counteracted the catabolic effects of endurance training, promoting muscle hypertrophy. Protein intake after exercise stimulates the synthesis of muscle protein by providing essential amino acids, which activate the mechanistic target of the rapamycin (mTOR) pathway crucial for muscle repair and growth.
However, they acknowledged the study’s limitation in the absence of biochemical markers such as mTOR, suggesting that future research should incorporate biochemical analyses for a deeper understanding of the molecular mechanisms driving physiological changes.
Journal: Nutrients
“Protein Supplementation Increases Adaptations to Low-Volume, Intra-Session Concurrent Training in Untrained Healthy Adults: A Double-Blind, Placebo-Controlled, Randomized Trial”
doi: 10.3390/nu16162713
Authors: Reljic, D. et al.
