Low-intensity blood flow restriction calf muscle training leads to similar functional and structural adaptations than conventional low-load strength training: A randomized controlled trial

Abstract

The purpose of this study was to investigate whether a six-week, twice weekly resistance training (4 sets at 30% 1-RM until failure) with practical blood flow restriction (BFR) using 7cm wide cuffs with a twist lock placed below the patella is superior to training without BFR (NoBFR) concerning muscle mass and strength gains in calf muscles. A two-group (BFR n = 12, mean age 27.33 (7.0) years, training experience 7.3 (7.0) years; NoBFR n = 9, mean age 28.9 (7.4) years, training experience 7.1 (6.6) years) randomized matched pair design based on initial 1-RM was used to assess the effects on structural and functional adaptations in healthy males (Perometer calf volume [CV], gastrocnemius muscle thickness using ultrasound [MT], 7-maximal hopping test for leg stiffness [LS], 1-RM smith machine calf raise [1-RM], and visual analogue scale as a measure of pain intensity [VAS]). The mean number of repetitions completed per training session across the intervention period was higher in the NoBFR group compared to the BFR group (70 (16) vs. 52 (9), p = 0.002). VAS measured during the first session increased similarly in both groups from first to fourth set (p<0.001). No group effects or time×group interactions were found for CV, MT, LS, and 1-RM. However, there were significant time effects for MT (BFR +0.07 cm; NoBFR +0.04; p = 0.008), and 1-RM (BFR +40 kg; NoBFR +34 kg; p<0.001). LS and CV remained unchanged through training. VAS in both groups were similar, and BFR and NoBFR were equally effective for increasing 1-RM and MT in trained males. However, BFR was more time efficient, due to lesser repetition per training session.

Blood Flow Restriction Resistance Training in Tendon Rehabilitation: A Scoping Review on Intervention Parameters, Physiological Effects, and Outcomes

“…Two case reports investigated BFRT with tendon ruptures, one on biceps tendon rupture (Wentzell, 2018 ) and one on Achilles tendon rupture (Yow et al, 2018 ). Eight studies investigated the effects of BFRT on healthy tendons, five on the Achilles tendon, including four RCTs (Centner et al, 2019b ; Chulvi-Medrano et al, 2020 ; Gavanda et al, 2020 ; Picon-Martinez et al, 2021 ) and one cross-sectional study (Canfer et al, 2021 ), one RCT on the patellar tendon (Centner et al, 2021 ), one RCT on the supraspinatus tendon (Brumitt et al, 2020 ), and one cohort study on the patellar tendon (Kubo et al, 2006 ). The sample sizes of included studies ranged from 1 to 56, with only 12 participants in total for tendon pathologies out of a total of 292 participants, with most included participants having healthy tendons.…”

“…The sample sizes of included studies ranged from 1 to 56, with only 12 participants in total for tendon pathologies out of a total of 292 participants, with most included participants having healthy tendons. All included studies investigated the effects of a LL-BFRT intervention, five in isolation (Sata, 2005 ; Wentzell, 2018 ; Yow et al, 2018 ; Cuddeford and Brumitt, 2020 ; Skovlund et al, 2020 ) four compared with LL-RT (Brumitt et al, 2020 ; Chulvi-Medrano et al, 2020 ; Gavanda et al, 2020 ; Canfer et al, 2021 ), three compared with HL-RT (Kubo et al, 2006 ; Centner et al, 2019b , 2021 ), and one with both LL-RT and HL-RT (Picon-Martinez et al, 2021 ). The duration of BFRT interventions ranged from a single session to 14 weeks.…”

Physiological adaptations and myocellular stress in short-term, high-frequency blood flow restriction training: A scoping review

“…As a result of the study designs employed comparing failure to non-failure work-matched protocols, a favorable adaptation profile was consistently observed in the HF-BFR condition compared to the low-intensity control condition (Table 2). Therefore, it is unknown whether the positive adaptations observed is a specific effect of BFR or the product of comparing failure-to non-failure exercise given longitudinal studies have shown similar musculoskeletal benefits when low-intensity exercise is performed to failure with-and without BFR in the upper and lower limbs [50,51] as well as when comparing non-failure BFR to failure BFR protocols [52].…”

Practical Blood Flow Restriction Training: New Methodological Directions for Practice and Research

“…The authors additionally used an ultrasound system to ensure that the arterial blood flow was not occluded at this pressure. This technique was later used in a few studies [ 39 , 40 ]. Despite the precautions used by the authors, this technique has some limitations.…”

“…In analyzing muscle damage, Wilson et al [ 19 ] demonstrated that soreness, power and muscle swelling were similar between low-load resistance exercise with and without pBFR; in addition, Behringer et al [ 38 ] demonstrated that after 6 weeks of sprint training, the heart-type fatty acid-binding protein (h-FABP) was significantly lower in the group that trained with pBFR than in the control group, with similar responses between groups regarding cortisol. Additionally, studies have found similar acute pain responses between low-load resistance exercise with and without pBFR [ 26 , 40 ]; furthermore, the high-load resistance exercise induces greater pain scores than low-load resistance exercise with pBFR [ 26 ]. Considering cardiovascular events, studies have compared high-load resistance exercise with low-load resistance exercise with pBFR, noting that post-exercise acute responses are similar between the exercise protocols, in relation to autonomic modulation [ 25 ], as well as on arterial stiffness and brachial systolic or diastolic blood pressure [ 24 ].…”