Most (but not all) swimmers find swimming with a pull-buoy between their legs faster or easier. The main reason is that the extra buoyancy helps keep your legs higher in the water, reducing drag. But there is second reason why.
Swimming with a pull buoy forces you to keep your legs together and so stops scissor kicks occurring when you swim. Swimmers with a scissor kick very rarely appreciate they part their legs in this manner but doing so creates a huge amount of drag akin to opening up a parachute behind you:
This is a very common problem but is sometimes missed by coaches on the pool deck as it happens so quickly within the stroke and the low viewing angle from the pool deck can make it difficult to spot. In fact on our recent clinic series 48% of swimmers had a significant scissor kick in their stroke that was easily spotted when viewed from overhead video analysis.
Fixing Scissor Kicks
A scissor kick is caused by a loss of balance, normally whilst breathing. The loss of balance is caused by your lead hand crossing the centre line in front of the head:
The scissor kick stabilises you again a fraction of a second later and stops you rolling onto your back. You probably won't even be aware you're parting your legs because at that moment all you're thinking about is 'give me air!':
The key to fixing a scissor kick is to remove the crossover of your lead hand whilst you are breathing. An excellent drill to work on removing the crossover is kicking on your side with fins on, drawing your shoulder blades together and back to bring the lead arm straight. You can find out more about that exercise on our DVDs and in our book, or on this blog post.
Once you've removed the crossover the scissor kick can sometimes linger on as a habit, so as you swim visualise keeping your legs straight and toes pointed, kicking from the hip. As you kick, make sure the big toes brush past each other in a nice rhythm 'tap tap tap'.
Give these exercises a go even if you don't think you have a scissor kick in your stroke. You may be surprised at what you find!