The purpose of this study was to investigate the effect of specific collagen peptides (SCP) combined with resistance training (RT) on changes in tendinous and muscular properties. In a randomized, placebo‐controlled study, 40 healthy male volunteers (age: 26.3 ± 4.0 years) completed a 14 weeks high‐load resistance training program. One group received a daily dosage of 5g SCP while the other group received 5g of a placebo (PLA) supplement. Changes in Achilles tendon cross‐sectional area (CSA), tendon stiffness, muscular strength, and thickness of the plantar flexors were measured. The SCP supplementation led to a significantly (p = 0.002) greater increase in tendon CSA (+11.0%) compared with the PLA group (+4.7%). Moreover, the statistical analysis revealed a significantly (p = 0.014) greater increase in muscle thickness in the SCP group (+7.3%) compared with the PLA group (+2.7%). Finally, tendon stiffness and muscle strength increased in both groups, with no statistical difference between the groups. In conclusion, the current study shows that the supplementation of specific collagen peptides combined with RT is associated with a greater hypertrophy in tendinous and muscular structures than RT alone in young physically active men. These effects might play a role in reducing tendon stress (i.e., deposition of collagen in load‐bearing structures) during daily activities.

Purpose: Recent evidence indicates that low‐load blood flow restriction (LL‐BFR) training elicits an anabolic response in tendinous tissue. The purpose of the present study was to investigate the hypertrophic pattern induced in the Achilles tendon by LL‐BFR, in comparison with the regional hypertrophy typically observed with conventional high‐load (HL) resistance training.Methods: N = 40 male participants were randomly and concealed allocated to one of two groups: LL‐BFR training (20–35% one‐repetition maximum/1RM) or HL training (70–85% 1RM). The training was completed three times per week for a total of 14 weeks. Before and after the training period, Achilles tendon morphology was assessed using magnetic resonance imaging along the entire tendon length. Additionally, dynamic strength measures of the plantar flexors were evaluated.Results: In line with previous findings, dynamic plantar flexion strength was improved to a comparable extent in both groups (LL‐BFR: 43.6%; HL: 43.5%). The results also confirmed significant increases in Achilles tendon cross‐sectional area with LL‐BFR (+5.2%). Moreover, they revealed that the hypertrophic pattern obtained with LL‐BFR was similar to regional changes seen with conventional HL training.Conclusion: The present findings point towards the notion that despite the low loads being applied, LL‐BFR training induces Achilles tendon hypertrophy by potentiating anabolic responses in the same regions as with conventional high‐load training. Future studies are needed to (i) focus on the potential mechanisms underlying these tendon morphology changes and (ii) apply and evaluate LL‐BFR training in clinical populations to validate these results in rehabilitative settings.

Bioactive peptides are physiologically active peptides mostly derived from proteins following gastrointestinal digestion, fermentation or hydrolysis by proteolytic enzymes. It has been shown that bioactive peptides can be resorbed in their intact form and have repeatedly been shown to have a positive effect on health-related parameters such as hypertension, dyslipoproteinemia, inflammation and oxidative stress. In recent years, there has been increasing evidence that biologically active peptides could also play an important role in sports nutrition. Current studies have shown that bioactive peptides could have a positive impact on changes in body composition and muscular performance, reduce muscle damage following exercise and induce beneficial adaptions within the connective tissue. In the following overview, potential mechanisms as well as possible limitations regarding the sports-related effect of bioactive peptides and their potential mechanisms are presented and discussed. In addition, practical applications will be discussed on how bioactive peptides can be integrated into a nutritional approach in sports to enhance athletic performance as well as prevent injuries and improve the rehabilitation process.

Background: First evidence indicates that the supplementation of specific collagen peptides (SCP) is associated with a significant improvement in running performance in physically active women; however, it is unclear if the same is true in males. The purpose of the present study was to investigate the effects of a concurrent training program including 60 min of continuous moderate intensity running training and 15 min of dynamic resistance training combined with supplementation of SCP on parameters of running performance in moderately trained males. Methods: In a double-blind, placebo-controlled, randomized trial, participants performed a 12 weeks concurrent training and ingested 15 g of SCP [treatment group (TG)] or placebo [control group (CG)] daily. Before and after the intervention, running endurance performance was measured by a 1-h time trial on a running track. Velocity at the lactate threshold (V_LT) and at the individual anaerobic threshold (V_IAT) were assessed on a treadmill ergometer. Body composition was evaluated by bioelectrical impedance analysis. Results: Thirty-two men (28.4 ± 5.2 years) completed the study and were included in the analysis. After 12 weeks, TG had a statistically significant (p ≤ 0.05) higher increase in running distance (1727 ± 705 m) compared to the CG (1018 ± 976 m) in the time trial. V_LT increased in the TG by 0.680 ± 1.27 km h⁻¹ and slightly decreased by − 0.135 ± 0.978 km h⁻¹ in the CG, resulting in statistically significant group differences (p ≤ 0.05). A significantly higher improvement in V_IAT (p ≤ 0.05) was shown in the TG compared with the CG only (1.660 ± 1.022 km h⁻¹ vs 0.606 ± 0.974 km h⁻¹; p ≤ 0.01). Fat mass decreased (TG − 1.7 ± 1.6 kg; CG − 1.2 ± 2.0 kg) and fat free mass increased (TG 0.2 ± 1.2 kg; CG 0.5 ± 1.3 kg) in both groups with no significant group differences. Conclusion: In summary, supplementation with 15 g of SCP improved running performance in a 1-h time trial and enhanced indicators of endurance capacity at submaximal exercise intensities such as an increased velocity at the lactate as well as the anaerobic threshold more effectively than CT alone. Trial registration: ETK: 123/17; DRKS-ID: DRKS00015529 (Registered 07 November 2018—Retrospectively registered); https://drks.de/search/de/trial/DRKS00015529

Objective: The extracellular matrix is essential for skeletal muscle function, providing structural support and facilitating force transmission from muscle fibers to tendons and the skeletal system. Collagen structures, known for their high plasticity, adapt to various stimuli, including mechanical loading during high-load resistance training. The present study aimed to assess the impact of specific collagen peptide (SCP) supplementation, combined with resistance training, on the levels of intramuscular collagen (COL) types I, III, and IV, and to assess the change in intramuscular fibroblast content. Methods: In a randomized, placebo-controlled study, 29 healthy male participants completed 12-week high-load resistance training (70-85% of 1 repetition maximum) with daily supplementation of 15g of SCP or placebo (PLA). Before and after the intervention period, muscle biopsies from the vastus lateralis muscle were obtained to quantify intramuscular collagen amount and fibroblast density. Results: SCP supplementation together with exercise led to increased (p = 0.026) collagen type I content (29.8%) compared to training with placebo (9.9%). Collagen types III and IV content increased significantly across the pooled sample (p < 0.05) with no significant group x time interaction. Fibroblast density did not change over the time course of intervention, either within or between groups. Conclusion: Endomysial collagen type I content increased in response to resistance training when supplemented with SCP compared to placebo. The observed increase in intramuscular collagen content may contribute to improved structural support of skeletal myofibers.