I have a client who is an open water swimmer whose goal was to improve her swimming strength.
Here is the approach we took as far as training was concerned.
We focused on resistance training for endurance as this type of training transfers well into the water. I incorporated balance exercises on the BOSU ball in a prone position as this is the position that she is in when she swims.
However, the most important thing for her to do was to simply swim.
In exercise science there is a principle that states that the body will adapt according to the way we train it. So, if you want to improve your swimming, swim more.
It probably won’t be a bad idea to hire a swimming coach.
All the best!