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1.
Sports Med Open ; 9(1): 103, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935999

RESUMO

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 (VLT) and at the individual anaerobic threshold (VIAT) 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. VLT 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 VIAT (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.

2.
Eur J Sport Sci ; 23(12): 2329-2339, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37424319

RESUMO

ABSTRACTThe purpose of this study was to investigate the effect of a supplementation with specific collagen peptides (SCP) combined with resistance training (RT) on changes in structural properties of the patellar tendon. Furthermore, tendon stiffness as well as maximal voluntary knee extension strength and cross-sectional area (CSA) of the rectus femoris muscle were assessed. In a randomized, placebo-controlled study, 50 healthy, moderately active male participants completed a 14-week resistance training program with three weekly sessions (70-85% of 1 repetition maximum [1RM]) for the knee extensors. While the SCP group received 5g of specific collagen peptides daily, the other group received the same amount of a placebo (PLA) supplement. The SCP supplementation led to a significant greater (p < 0.05) increase in patellar tendon CSA compared with the PLA group at 60% and 70% of the patellar tendon length starting from the proximal insertion. Both groups increased tendon stiffness (p < 0.01), muscle CSA (p < 0.05) and muscular strength (p < 0.001) throughout the intervention without significant differences between the groups. The current study shows that in healthy, moderately active men, supplementation of SCP in combination with RT leads to greater increase in patellar tendon CSA than RT alone. Since underlying mechanisms of tendon hypertrophy are currently unknown, further studies should investigate potential mechanisms causing the increased morphology adaptions following SCP supplementation.Trial registration: German Clinical Trials Register identifier: DRKS00029244..


A daily supplementation of 5 g of specific collagen peptides during 14 weeks of high-load resistance training increase patellar tendon hypertrophy compared to the same training regimen and placebo.The resistance training-induced CSA increase, which was most pronounced on proximal and medial patellar tendon sites, is uniformly potentiated along the entire tendon length by supplementation.Patellar tendon stiffness, CSA of the rectus femoris muscle and maximal voluntary knee extension strength increase due to training independently from supplementation.Increased tendon CSA as a result of a stimulating effect of the supplementation with specific collagen peptides on collagen synthesis might be able to decrease tendon stress and support tendon healing.


Assuntos
Ligamento Patelar , Treinamento Resistido , Humanos , Masculino , Ligamento Patelar/anatomia & histologia , Ligamento Patelar/fisiologia , Força Muscular/fisiologia , Colágeno/farmacologia , Poliésteres/farmacologia , Músculo Esquelético/fisiologia
3.
Scand J Med Sci Sports ; 33(6): 848-856, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36703264

RESUMO

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.


Assuntos
Tendão do Calcâneo , Treinamento Resistido , Humanos , Masculino , Treinamento Resistido/métodos , Fluxo Sanguíneo Regional/fisiologia , Força Muscular/fisiologia , Tendão do Calcâneo/diagnóstico por imagem , Hipertrofia , Músculo Esquelético/fisiologia
4.
Front Physiol ; 13: 838004, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35480041

RESUMO

Previous evidence suggests that resistance training in combination with specific collagen peptides (CP) improves adaptive responses of the muscular apparatus. Although beneficial effects have been repeatedly demonstrated, the underlying mechanisms are not well understood. Therefore, the primary objective of the present randomized trial was to elucidate differences in gene expression pathways related to skeletal muscle signal transduction following acute high-load resistance exercise with and without CP intake. Recreationally active male participants were equally randomized to high-load leg extension exercise in combination with 15 g CP or placebo (PLA) supplementation. Muscle biopsies from the vastus lateralis muscle were obtained at baseline as well as 1, 4 and 24 h post exercise to investigate gene expression using next generation sequencing analysis. Several important anabolic pathways including PI3K-Akt and MAPK pathways were significantly upregulated at 1 and 4 h post-exercise. Significant between-group differences for both pathways were identified at the 4 h time point demonstrating a more pronounced effect after CP intake. Gene expression related to the mTOR pathway demonstrated a higher visual increase in the CP group compared to PLA by trend, but failed to achieve statistically significant group differences. The current findings revealed a significantly higher upregulation of key anabolic pathways (PI3K-Akt, MAPK) in human skeletal muscle 4 h following an acute resistance training combined with intake of 15 g of specific collagen peptides compared to placebo. Further investigations should examine potential relationships between upregulated gene expression and changes in myofibrillar protein synthesis as well as potential long-term effects on anabolic pathways on the protein level.

5.
Scand J Med Sci Sports ; 32(7): 1131-1141, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35403756

RESUMO

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.


Assuntos
Tendão do Calcâneo , Treinamento Resistido , Tendão do Calcâneo/fisiologia , Adulto , Colágeno , Suplementos Nutricionais , Humanos , Masculino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Peptídeos , Poliésteres/farmacologia , Adulto Jovem
6.
Med Sci Sports Exerc ; 54(4): 582-589, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34772900

RESUMO

INTRODUCTION: Low-load resistance training with blood flow restriction (LL-BFR) has emerged as a viable alternative to conventional high-load (HL) resistance training regimens. Despite increasing evidence confirming comparable muscle adaptations between LL-BFR and HL resistance exercise, only very little is known about tendinous mechanical and morphological adaptations after LL-BFR. Therefore, the aim of the present study was to examine the effects of 14 wk of LL-BFR and HL training on patellar tendon adaptations. METHODS: Twenty-nine recreationally active male participants were randomly allocated into the following two groups: LL-BFR resistance training (20%-35% one-repetition maximum (1RM)) or HL resistance training (70%-85% 1RM). Both groups trained three times per week for 14 wk. One week before and after the intervention, patellar tendon mechanical and morphological properties were assessed via ultrasound and magnetic resonance imaging. In addition, changes in muscle cross-sectional area were quantified by magnetic resonance imaging and muscle strength via dynamic 1RM measurements. RESULTS: The findings demonstrated that both LL-BFR and HL training resulted in comparable changes in patellar tendon stiffness (LL-BFR: +25.2%, P = 0.003; HL: +22.5%, P = 0.024) without significant differences between groups. Similar increases in tendon cross-sectional area were observed in HL and LL-BFR. Muscle mass and strength also significantly increased in both groups but were not statistically different between HL (+38%) and LL-BFR (+34%), except for knee extension 1RM where higher changes were seen in LL-BFR. CONCLUSIONS: The present results support the notion that both HL and LL-BFR cause substantial changes in patellar tendon properties, and the magnitude of changes is not significantly different between conditions. Further studies that examine the physiological mechanisms underlying the altered tendon properties after LL-BFR training are needed.


Assuntos
Ligamento Patelar , Treinamento Resistido , Humanos , Masculino , Força Muscular/fisiologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Ligamento Patelar/diagnóstico por imagem , Músculo Quadríceps/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Treinamento Resistido/métodos
7.
Nutrients ; 13(11)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34836255

RESUMO

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.


Assuntos
Peptídeos/farmacologia , Ciências da Nutrição e do Esporte , Desempenho Atlético/fisiologia , Composição Corporal/efeitos dos fármacos , Tecido Conjuntivo/efeitos dos fármacos , Exercício Físico/fisiologia , Humanos , Inflamação , Músculos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Proteínas , Esportes
8.
J Appl Physiol (1985) ; 127(6): 1660-1667, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31725362

RESUMO

Low-load blood flow restriction (LL-BFR) training has gained increasing interest in the scientific community by demonstrating that increases in muscle mass and strength are comparable to conventional high-load (HL) resistance training. Although adaptations on the muscular level are well documented, there is little evidence on how LL-BFR training affects human myotendinous properties. Therefore, the aim of the present study was to investigate morphological and mechanical Achilles tendon adaptations after 14 wk of strength training. Fifty-five male volunteers (27.9 ± 5.1 yr) were randomly allocated into the following three groups: LL-BFR [20-35% of one-repetition maximum (1RM)], HL (70-85% 1RM), or a nonexercising control (CON) group. The LL-BFR and HL groups completed a resistance training program for 14 wk, and tendon morphology, mechanical as well as material properties, and muscle cross-sectional area (CSA) and isometric strength were assessed before and after the intervention. Both HL (+40.7%) and LL-BFR (+36.1%) training induced significant increases in tendon stiffness (P < 0.05) as well as tendon CSA (HL: +4.6%, LL-BFR: +7.8%, P < 0.001). These changes were comparable between groups without significant changes in Young's modulus. Furthermore, gastrocnemius medialis muscle CSA and plantar flexor strength significantly increased in both training groups (P < 0.05), whereas the CON group did not show significant changes in any of the evaluated parameters. In conclusion, the adaptive change in Achilles tendon properties following low-load resistance training with partial vascular occlusion appears comparable to that evoked by high-load resistance training.NEW & NOTEWORTHY Low-load blood flow restriction (LL-BFR) training has been shown to induce beneficial adaptations at the muscular level. However, studies examining the effects on human tendon properties are rare. The findings provide first evidence that LL-BFR can increase Achilles tendon mechanical and morphological properties to a similar extent as conventional high-load resistance training. This is of particular importance for individuals who may not tolerate heavy training loads but still aim for improvements in myotendinous function.


Assuntos
Tendão do Calcâneo/fisiologia , Adaptação Fisiológica/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Adolescente , Adulto , Humanos , Masculino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adulto Jovem
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