Date of Award


Document Type



Physical Therapy

First Advisor

Gary Schindler


Blood flow restriction therapy (BFR), Physical Therapy, Repetition Maximum (RM), Infraspinatus,extensor carpi radialis brevis (ECRB) , Electromyography (EMG) , External Rotation (ER)


Purpose/Hypothesis: Blood flow restriction therapy (BFR) has become a popular means of strength training and intervention used by physical therapists, athletic trainers and body builders. BFR allows for high intensity resistance training at a low intensity training level. It has been shown that BFR increases muscular hypertrophy and strength due to the vascular occlusion that occurs during BFR application. When performing BFR a pressurized tourniquet cuff is applied to the proximal portion of the selected limb. Individuals complete exercise between 20-40% of their 1 repetition maximum (RM) while utilizing the BFR cuff for improvements in muscular strength. Most BFR research has focused on the effects of BFR on distal musculature. The purpose of the following study is to examine the effects of BFR on the musculature activity of the infraspinatus and extensor carpi radialis brevis (ECRB) with the use of electromyography (EMG).

Materials/Methods: Twenty subjects, 12 females and 8 males, with ages ranging from 21 to 31 years old participated in the BFR and electromyography (EMG) analysis. A shoulder external rotation (ER) one-repetition maximum (RM) was identified. EMG electrodes were placed on infraspinatus and extensor carpi radialis brevis muscles. Participants performed shoulder external rotation in side lying until they completed two consecutive training errors or reached volitional fatigue.

Results: No statistical significance difference in slope, amplitude, frequency and number of repetitions were found between exercise completion with and without BFR. Therefore, no significant difference in fatigue was noted between exercise completion with and without BFR. DocuSign Envelope ID: 4F491E17-8B7B-4265-B46D-A6CC3508DE7B IX.

Discussion: No statistical significant difference was found in the slope, amplitude, and frequency for EMG activity, and number of reps with and without BFR. Limitations include a small non-diverse sample, and inconsistent trigger switch activation depicting beginning and ending of individual repetitions. Future research is needed to further examine the effects of BFR on distal musculature.