What is the clinical evidence from this study?

Study design: RCT. Intervention: Low-intensity interval training with blood flow restriction (BFR) vs. Low-intensity without BFR, high-intensity (HIT), and combined BFR+HIT. Primary outcome: Aerobic fitness (VO2max, Pmax, OBLA) and muscle strength.

What does this research mean for the field?

Low-intensity interval training with blood flow restriction simultaneously improves both aerobic fitness and muscle strength, an advantage not seen with high-intensity or combined training protocols. Novelty: ClaimNovelty.INCREMENTAL. Consensus alignment: ConsensusAlignment.NEUTRAL.

September 15, 2015Open Access

Short‐term low‐intensity blood flow restricted interval training improves both aerobic fitness and muscle strength

Key Result

Low-intensity interval training with blood flow restriction simultaneously improved aerobic fitness (VO2max 6%, Pmax 12%) and muscle strength (11%), whereas strength gains were absent in other groups.

Study Design

Type

RCT (n=37)

Structured PICO

Does low-intensity blood flow restricted interval training improve aerobic fitness and muscle strength compared to other interval training protocols in healthy subjects?

Population

37 subjects, mean age 23.8 ± 4 years, height 171.7 ± 9.5 cm, weight 70 ± 11 kg

Intervention

Low-intensity interval training with blood flow restriction (BFR, n=10), high-intensity interval training (HIT, n=10), or combined HIT and BFR (n=10, 50% BFR and 50% HIT) for 4 weeks (3 days a week)

Comparator

Low-intensity interval training without blood flow restriction (LOW, n=7) for 4 weeks (3 days a week)

Outcome

Maximal oxygen uptake (VO2max), maximal power output (Pmax), onset blood lactate accumulation (OBLA), and muscle strength before and after 4 weeks of trainingsurrogate

Short-term low-intensity interval training with blood flow restriction is uniquely capable of simultaneously improving both aerobic fitness and muscular strength.

Abstract

The present study aimed to analyze and compare the effects of four different interval-training protocols on aerobic fitness and muscle strength. Thirty-seven subjects (23.8 ± 4 years; 171.7 ± 9.5 cm; 70 ± 11 kg) were assigned to one of four groups: low-intensity interval training with (BFR, n = 10) or without (LOW, n = 7) blood flow restriction, high-intensity interval training (HIT, n = 10), and combined HIT and BFR (BFR + HIT, n = 10, every session performed 50% as BFR and 50% as HIT). Before and after 4 weeks training (3 days a week), the maximal oxygen uptake (VO2max ), maximal power output (Pmax ), onset blood lactate accumulation (OBLA), and muscle strength were measured for all subjects. All training groups were able to improve OBLA (BFR, 16%; HIT, 25%; HIT + BFR, 22%; LOW, 6%), with no difference between groups. However, VO2max and Pmax improved only for BFR (6%, 12%), HIT (9%, 15%) and HIT + BFR (6%, 11%), with no difference between groups. Muscle strength gains were only observed after BFR training (11%). This study demonstrates the advantage of short-term low-intensity interval BFR training as the single mode of training able to simultaneously improve aerobic fitness and muscular strength.