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Centner, C, Ritzmann, R, Gollhofer, A, and König, D. Effects of whole-body vibration training and blood flow restriction on muscle adaptations in women: a randomized controlled trial. J Strength Cond Res 34(3): 603-608, 2020-The purpose of the present randomized controlled trial was to investigate potential synergistic effects of whole-body vibration (WBV) training combined with blood flow restriction (BFR) on muscle mass and strength, and jump performance. Fifty healthy women (26.1 ± 4.6 years) were randomly allocated to one of the following experimental groups: WBV training combined with BFR (WBV + BFR) or WBV only. Before and after the 10-week training intervention, muscle cross-sectional area (CSA) of the vastus lateralis (VL) and gastrocnemius medialis (GM) was evaluated. Additionally, changes in muscle strength and jump performance were assessed before and after the intervention. The level of significance was set to p < 0.05. Vastus lateralis muscle CSA increased in both groups (p < 0.05). The increase in CSA was less pronounced after WBV than WBV + BFR, although the difference was not significant (p = 0.30). Likewise, GM CSA demonstrated comparable increases in both groups with a significant main effect of time (p < 0.05) but no interaction effect (p = 0.89). Assessment of muscular strength (p = 0.70) and jump performance (p = 0.40) did not reveal significant differences between the groups. The results of the present study indicate that the combination of WBV training with BFR shows a noticeable trend toward higher increases in muscle CSA compared with WBV alone. Despite the lack of significance, the results imply clinical relevance particularly in populations showing contraindications toward high training loads. This, however, needs to be confirmed in future research.

Blood flow restriction (BFR) training has been shown to induce favorable changes in muscle mass and strength with a considerably low training load (20 - 30% 1RM). However, it has never been evaluated if an additional post-exercise protein supplementation enhances the effects of this training regimen. Thirty healthy older men (60.1 ± 7.6 years) were enrolled in the 8-week intervention and randomly allocated to one of the following groups: low-load BFR training with protein (collagen hydrolysate) supplementation (BFR-CH), low-load BFR training with placebo (BFR-PLA), or a control group without training, but with protein supplementation (CON). Muscle cross-sectional area (CSA), muscle strength, circulating reactive oxygen species and IGF-1 were measured before and after the intervention. Muscle CSA increased in both BFR-CH and BFR-PLA groups by 6.7 ± 3.2 % (p < 0.001) and 5.7 ± 2.7 % (p < 0.001) respectively. No significant changes were observed in the CON group (1.1 ± 1.7 %, p = 0.124). Evaluation of isometric strength (p = 0.247), insulin-like growth factor 1 (p = 0.705) and the production of reactive oxygen species (p t1 = 0.229; p t2 = 0.741) revealed no significant interaction effect but a significant long-term time effect (p < 0.001). Our results demonstrate that BFR training is an effective alternative for increasing muscle CSA in older men. Although there was a trend towards greater muscle mass adaptations in the BFR-CH group, these findings showed no statistical significance. Further research with larger sample sizes is needed to confirm these results.

The aim was to investigate the effects of resistance exercise combined with supplementation of specific collagen peptides (SCP) on body composition and muscle strength in premenopausal women. In a double-blind, placebo-controlled, randomized trial 77 premenopausal women completed a 12-week resistance training (3 day/week) and ingested 15 g of SCP or placebo on a daily basis. Changes in body composition were determined by bioelectrical impedance analysis (BIA) and muscular strength by isometric strength testing. The treatment group (TG) significantly increased ( p < 0.001) their percentage of fat-free mass. Although the control group (CG) also showed a significant ( p < 0.01) gain in fat-free mass from pre- to post-training, the increase in the TG was significantly higher in an RMANOVA analysis ( p < 0.05). Regarding the change in percentage body fat, a significant decline was observed in both TG ( p < 0.001) and CG ( p < 0.01), with a significantly higher reduction in the TG ( p < 0.05). Subjects receiving 15 g of collagen peptides daily also showed a significantly higher gain in hand-grip strength compared to those performing resistance training only ( p < 0.05). In both groups, the gain in leg strength (TG = p < 0.001; CG = p < 0.01) was significant after 12 weeks with a more pronounced effect in the treatment group. In conclusion, resistance training in combination with supplementation of SCP induced a significantly higher increase in fat-free mass and hand-grip strength than resistance training and placebo supplementation. In addition, there was a significantly higher loss in fat mass and a more pronounced increase in leg strength in the treatment group compared to the control group.

Background: The combination of low-load resistance training with blood flow restriction (BFR) has recently been shown to promote muscular adaptations in various populations. To date, however, evidence is sparse on how this training regimen influences muscle mass and strength in older adults., Purpose: The purpose of this systematic review and meta-analysis was to quantitatively identify the effects of low-load BFR (LL-BFR) training on muscle mass and strength in older individuals in comparison with conventional resistance training programmes. Additionally, the effectiveness of walking with and without BFR was assessed., Methods: A PRISMA-compliant systematic review and meta-analysis was conducted. The systematic literature research was performed in the following electronic databases from inception to 1 June 2018: PubMed, Web of Science, Scopus, CINAHL, SPORTDiscus and CENTRAL. Subsequently, a random-effects meta-analysis with inverse variance weighting was conducted., Results: A total of 2658 articles were screened, and 11 studies with a total population of N = 238 were included in the meta-analysis. Our results revealed that during both low-load training and walking, the addition of BFR elicits significantly greater improvements in muscular strength with pooled effect sizes (ES) of 2.16 (95% CI 1.61 to 2.70) and 3.09 (95% CI 2.04 to 4.14), respectively. Muscle mass was also increased when comparing walking with and without BFR [ES 1.82 (95% CI 1.32 to 2.32)]. In comparison with high-load training, LL-BFR promotes similar muscle hypertrophy [ES 0.21 (95% CI - 0.14 to 0.56)] but lower strength gains [ES - 0.42 (95% CI - 0.70 to - 0.14)]., Conclusion: This systematic review and meta-analysis reveals that LL-BFR and walking with BFR is an effective interventional approach to stimulate muscle hypertrophy and strength gains in older populations. As BFR literature is still scarce with regard to potential moderator variables (e.g. sex, cuff pressure or training volume/frequency), further research is needed for strengthening the evidence for an effective application of LL-BFR training in older people.

Protein supplementation in combination with resistance training may increase muscle mass and muscle strength in elderly subjects. The objective of this study was to assess the influence of post-exercise protein supplementation with collagen peptides v. placebo on muscle mass and muscle function following resistance training in elderly subjects with sarcopenia. A total of fifty-three male subjects (72·2 (sd 4·68) years) with sarcopenia (class I or II) completed this randomised double-blind placebo-controlled study. All the participants underwent a 12-week guided resistance training programme (three sessions per week) and were supplemented with either collagen peptides (treatment group (TG)) (15 g/d) or silica as placebo (placebo group (PG)). Fat-free mass (FFM), fat mass (FM) and bone mass (BM) were measured before and after the intervention using dual-energy X-ray absorptiometry. Isokinetic quadriceps strength (IQS) of the right leg was determined and sensory motor control (SMC) was investigated by a standardised one-leg stabilisation test. Following the training programme, all the subjects showed significantly higher (P<0·01) levels for FFM, BM, IQS and SMC with significantly lower (P<0·01) levels for FM. The effect was significantly more pronounced in subjects receiving collagen peptides: FFM (TG +4·2 (sd 2·31) kg/PG +2·9 (sd 1·84) kg; P<0·05); IQS (TG +16·5 (sd 12·9) Nm/PG +7·3 (sd 13·2) Nm; P<0·05); and FM (TG -5·4 (sd 3·17) kg/PG -3·5 (sd 2·16) kg; P<0·05). Our data demonstrate that compared with placebo, collagen peptide supplementation in combination with resistance training further improved body composition by increasing FFM, muscle strength and the loss in FM.

The 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have demonstrated that the addition of blood flow restriction (BFR) to low-load (LL) resistance exercise leads to elevated levels of muscle hypertrophy and strength gains. In terms of main underlying mechanisms, metabolic accumulation and increased neuromuscular adaptations seem to play a primary role. However, this evidence is largely based on dynamic exercise conditions. Therefore, the main objective was to investigate the acute physiological adaptations following isometric LL-BFR exercise. Methods: Fifteen males participated in this cross-over trial and completed the following sessions in a random and counterbalanced order: isometric LL-BFR exercise (20% maximum voluntary contraction, MVC) and load matched LL exercise without BFR. Lactate levels, muscle activation as well as muscle swelling were recorded during the whole exercise and until 15 min post completion. Additionally, changes in maximal voluntary torque and ratings of perceived exertion (RPE) were monitored. Results: During exercise, EMG amplitudes (72.5 ± 12.7% vs. 46.3 ± 6.7% of maximal EMG activity), muscle swelling and RPE were significantly higher during LL-BFR compared to LL (p < 0.05). Lactate levels did not show significant group differences during exercise but revealed higher increases 15 min after completion in the LL-BFR condition (LL-BFR: + 69%, LL: + 22%) (p < 0.05). Additionally, MVC torque significantly decreased immediately post exercise only in LL-BFR (~ − 11%) (p < 0.05) but recovered after 15 min. Conclusions: The present results demonstrate that isometric LL-BFR causes increased metabolic, neuromuscular as well as perceptual responses compared to LL alone. These adaptations are similar to dynamic exercise and therefore LL-BFR represents a valuable type of exercise where large joint movements are contraindicated (e.g. rehabilitation after orthopedic injuries). [ABSTRACT FROM AUTHOR]

Figures 2 and 3 were transposed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]