Found this really useful article on the Growing Bodies blog about hip flexors.
The writer explains that they get tight and also “overactivity” in the hip flexor.
Overactivity means you are using your hip flexors too much and they give two situations where this can happen – it’s best to adjust the stroke so you un-learn these habits but that’s difficult.
Overactivity of hip flexors can come about under two different circumstances;
The rower does not achieve early rock over (due to timing issues or tight hamstrings) and then has to use the hip flexors to bring the pelvis to upright throughout the recovery and coming into the catch
When a rower begins the drive, they may lift their shoulders, losing the connection on the front of their abdominal wall, this results in a raising of the chest and a reliance on the hip flexors to stabilise the pelvis and spine through the drive rather than the gluteal and abdominal muscles – overusing the hip flexors through the drive makes it very difficult for the hip flexors to achieve early ‘rock over’ as they are still stabilising the spine at the end of the drive, the hip flexors often continue to be active as the rower attempts to tilt the pelvis during the recovery
Read the full article on Growing Bodies and how to do the stretches.