Blood flow restriction training is commonly thought of as a strength training tool but is there a use for aerobic athletes too?
Blood flow restriction (BFR) training or KAATSU training, has been around for almost half a century but has recently grown into a popular mainstream strength training and rehabilitation technique. But is it also a useful training technique for aerobic athletes?
There is some recent evidence to suggest that it might be the case however most of the studies have taken place with untrained populations. This makes it hard to determine if BFR training is effective at improving aerobic performance or if it’s just the fact untrained people are doing any form of training.
A new systematic review with meta-analysis published in the Journal of Exercise Science & Fitness aims to clarify if there is a benefit of combining BFR with endurance training by evaluating performance in trained athletes.
This systematic review followed PRISMA guidance and the protocol was pre-registered on PROSPERO. In total eight databases were used searched using the terms listed below. The full search strings used are available in full.
“Kaatsu”OR “bloodflow restriction” OR “tourniquets” OR “ischemia” OR”vascular occlusion” OR “occlusion training”) AND (“endurance” OR“VO2max”OR “aerobic”) AND (“sport”OR “athlete”)
Two independent reviewers completed the search with disagreements resolved through consensus. To be included within the review, studies were eligible if they met the following criteria:
- conducted in healthy injury free athletes
- involved athletes which had a VO2max of 38.0 and 45.0 ml/kg/min for women and men and taking part in sport 3x/wk for at least 3 years at regional level or better
- used VO2 max or direct endurance performance parameters as outcomes
- were randomised or non-randomised trials published in English, Portuguese or Spanish
- participants had at least 8 sessions of BFR training
Included studies was assessed using Cochrane’s Risk of Bias 2.0 tool with results showing that overall there were “some concerns” with the overall risk of bias of the included studies. The areas of concern are consistently to do with randomisation and reporting of outcomes.
In total ten studies were included within the review with six suitable for meta-analysis. From these studies a total of 207 athletes were included with 77.8% being male and the average age was 22.2 ± 2.2 years old. The participants were from a wide range of sports including middle and long distance running, futsal, soccer, basketball, rowing and sprinting. Most studies took place in Asian countries.
The results of the qualitative analysis suggests there is limited evidence to suggest blood flow restriction training improves aerobic capacity and performance. There were three variables regarding aerobic capacity used (VO2 max, vVO2 max and running economy) and seven variables regarding performance (time to exhausation, 30-s Wingate, multistate fitness performance, sprint performance and other sport specific measures). If anything the conflicting results suggest that blood-flow restriction was inferior to normal training.
The meta-analysis confirmed these findings by showing that there were no statistical differences between BFR and non-BFR groups. Subgroup analysis according to intensity or training (high vs low) also demonstrated no significant difference between the two groups. The good thing though is that all athletes improved when taking part in regular training.
This systematic review with meta-analysis revealed that training with blood flow restriction did not improve aerobic parameters any more than non-blood flow restriction training in athletes. That being said BFR training isn’t commonly used by aerobic athletes. the technique is more often used for strength training where there is a much clearer use. You can find out more about this by taking part in the course linked to below.