Strong but relaxed
Your core position is important to create a level of stability in your swimming position in which everything works from. The core needs to ‘strong but relaxed’ so not so tense as if you are going for a plank pb and not so relaxed that your back arches and your low body fish tails around in the water.
Get the right level of activation and it will help you
- hold length in your body
- keep your kick together and higher in the water
- assist a strong body rotation
Sometimes by focusing on head position (water at the hairline) this can help you hold stability of the core, so that you don't submarine/ submerge or go up and down as you alternate your arm stroke.
Weak core can create
- The lower body to fish tail through the water (snaking)
- Unstable kick technique as the legs just follow the hips fish tailing behind the upper body
- Little to no timing between the upper body (shoulders) and hips and kick