There always seems to be some controversy surrounding kicking in Freestyle swimming. In the TI forums, someone posed a query about kicking and here is how I answered it, with some minor edits:
Some thoughts about kicking that I’ve discovered:
1. There are those who can kick to propel themselves at speed, and those who cannot.
2. There are many reasons why someone cannot propel themselves at speed, some physical, some neurological.
3. The younger you are, the more likely you can develop the correct physical and neurological attributes to enable kicking for speed. Entering swimming when you are older means you will most likely have a harder time developing attributes for speed generation via kicking.
4. Some theorize that bigger feet can propel you faster. I’m not sure this has been conclusively proven that big feet always make you fast via kicking since there are other elements involved besides big feet, but there are definite advantages to being able to have more surface area for moving water.
5. In my experience, poor balance will result in negating any kicking advantage you might obtain. If you’re even gonna have a chance at speed via kicking, you better have your act together in balance. This goes for flutter kicking in SG, or Skate. It also applies to kicking with a board. If you are dragging your body in the water behind the kickboard, you’re gonna have a hard time obtaining speed while kicking behind it.
6. Thus, one bad aspect of kicking with a board is that in order to get your body up, you’re most likely going to have to overextend your back and arch to get your hips and legs up horizontal. This can be VERY bad for your back. To combat this, you could keep your head down in the water but then you have to tip your head up or to the side to take the occasional breath.
7. There is a risk that if you imprint overextending on the kickboard, it can ruin your posture for regular swimming. The majority of the population in today’s society already exhibits overextended backs (ie. “sway”). I do not think it’s a good idea to reinforce already a bad postural aspect.
8. Some physical and neurological attributes:
a. Ankle flexibility seems to be a major element. You must also be able to point your feet and toes and keep them pointed without straining other muscles while swimming (ie. no calf cramps!).
b. Proper movement pattern for kicking, very unlike any other kind of movement pattern on land.
c. Proper mobility and strength in the lower body, from hips to feet.
d. Ability to move legs rapidly enough in that movement pattern from a physical conditioning standpoint. Moving your legs so much requires more oxygen and energy and thus there is some fitness you will have to develop in order to kick for a long time.
e. Timing some of the kicks to the arm stroke to generate power spearing forward. If 2BK, then all of the kicks, 1 each stroke, is timed to the spear.
9. If you are kick challenged, then don’t waste time developing your kick like someone who has been swimming since they were a kid or someone who has mastered the 6BK. Go to the 2BK immediately.
9a. If you are finding that kicking isn’t moving you forward all that fast, then also don’t bother. You will probably find that kicking will use up resources faster than you want, versus getting you more speed.
10. You should also ask yourself why would you want to kick in Freestyle swimming. If you are trying to be the fastest for short course racing, then it may be worthwhile. If you are a triathlete and need to save the legs for the bike and run, then kicking might not be desirable.
11. If you are kick challenged, that doesn’t mean you couldn’t develop a kick. Like it or not, kicking is a valid swimming skill and if someone wants to learn, then by all means go for it.
I was kick challenged but then over the years of working in TI, i could actually start moving myself across the pool with kicking! The things I had to adjust for myself were:
a. If I kicked in Skate, I had to spear much deeper, like 30-40 deg than for regular swimming. This would ensure I had my hips really high and a great horizontal position in the water.
b. I had to metabolically prepare for constant and fast movement of my legs, and at a rate that was higher than I was accustomed to. This rate was much higher than for running. And I had to maintain it while I could not get constant air due to being face down longer than I would for a land activity.
c. I learned that kicking on my back was different than kicking on my stomach. If you kick on your back, you need to also exert kicking force to the back of the leg in addition to kicking forward. This helps bring your hips up. Also, this aspect applies to kicking in Backstroke – the first time I was drilling Backstroke, I could not even move! But then Coach Shinji told me I needed more down kick, or when on my back I needed to kick to the rear of my legs versus only to the front, and that fixed everything.
So it can be trained, and there are ways to train for 6BK that are optimized. The later in life you start swimming, the more time you’re going to spend developing the basic attributes for kicking. I do think it is possible at any age to do so. It’s just that most people are too impatient to work at it and arguably you can swim pretty fast without kicking so much.