The immediate physiological response to eccentrically loaded blood-flow restriction training in healthy

Background Strength training with accentuated eccentric loading under blood-flow restriction (E-BFR) concurrently augments intramuscular mechanical and metabolic stress. This might potentially increase training outcomes.

Aim: To investigate the acute physiological response to and feasibility of E-BFR in both younger (<50 years), and older (≥50 years) healthy individuals.

Methods Participants conducted a crossover trial with three study visits. After a baseline visit, two strength exercise visits on a hydraulic leg press (4 sets with max 12 repetitions, 45 sec inter-set break, concentric load: 30% of concentric 1-RM, eccentric load: 30% of eccentric 1-RM) followed. One as E-BFR (70% of arterial occlusion pressure) and one without BFR. Primary outcome was minute ventilation (VE) during exercise, continuously measured with a metabolic cart. We secondarily investigated comprehensive cardiorespiratory parameters, muscle tissue saturation (SmO₂), and muscle contractile fatigue.

Results 40 participants completed the study, 24 younger (12 females, mean [SD] age 32 years, VO₂max 47 ml/min/kg), 16 older (8 females, 62 years, VO₂max 32 ml/min/kg). The study is ongoing, no adverse events occurred, no participant discontinued the trial. All data are B [95% CI] from linear mixed modelling. VE was significantly higher with E-BFR from set three until end exercise in older (set3: 7.5 [8.7, 15.9] l/min, break3: 9.9 [6.7, 13.2] l/min, set4: 12.5 [9.1, 15.8] l/min), and younger (set3: 12.3 [8.7, 15.9] l/min, break3: 10.2 [6.6, 13.9] l/min, set4: 17.0 [13.4, 20.7] l/min). SmO₂ was significantly lower throughout exercise with E-BFR in older participants (set1: –7 [–9, –4]%, break1: –12 [–14, –9]%, set2: –8 [–11, –5]%, break2: –13 [–16, –10]%, set3: –10 [–13, –7]%, break3: –14 [–17, –12]%, set4: –11 [–14, –9]%), and in younger from the first break (break1: –9 [–12, –6]%, set2: –6 [–9, –3]%, break2: –11 [–14, –8]%, set3: –8 [–11, –5]%, break3: –14 [–17, –11]%, set4: –8 [–11, –5]%). E-BFR induced significantly more quadriceps contractile fatigue (Δtorque post-pre exercise: –18 [–34, –1] Nm in younger, –21 [–36, 6] Nm in older).

Conclusions E-BFR is feasible in both younger and older individuals and elicits pronounced acute physiological stimuli when compared to load-matched exercise without BFR. Future studies may investigate E-BFR in clinical populations.

Publication History

Article published online:
23 October 2025