Foam Rolling for Hamstrings
One of the classic tests of hamstring flexibility is the Sit and Reach test. in 2014, researchers set out to assess whether foam rolling can increase your hamstring flexibility, as measured by the Sit and Reach. here are some quotes form the study:
A main effect for testing time (p<0.0001) illustrated that the use of the roller-massager resulted in a 4.3% increase in ROM (Range of Motion).
There was a trend (p=0.069) for 10s of rolling duration to increase ROM more than 5s rolling duration.
The roller-massager can provide statistically significant increases in ROM, particularly when used for a longer duration.