Other than reading the TI book and watching the video about 6 years ago, I’m largely a self-taught swimmer – with no doubt, a large collection of bad habits. FWIW, my HIM swim PR is 30:00.
I just started a masters swim stroke clinic conducted as a fund raiser for the local HS swim team. We get critiqued by the coaches, video taped, given drills, etc.
Anyway, my question relates to the physics of the “catch” position and its affect on body position (i.e. “balance”) in the water.
TI’s early and deep entry results in the catch beginning deep under the surface of the water. My current, home-brewed stroke isn’t strictly TI any longer, but for better or worse I retain the habit of starting my pull deep. As the deep pull begins, the force vector (on the pulling forearm) is forwards and angled slightly downwards. This results in a torque on the body rotating the head down and hips/legs up giving a better body position.
My new coach pointed this out in my stroke and instead is trying to get me to alter my stroke so that I still reach out long before the catch, but begin the catch much shallower (closer to the surface). I’m slower when I try this right now, but I’m sure that’s just because I haven’t perfected the new form. But what about the angles? Pulling from shallow water results in a force on my forearm with an upwards component and creates a torque that sinks my hips and legs.
Clearly, the “shallow catch” must be effective as it’s used by top swimmers, but what about the force angles? What am I missing?
Perhaps you are keeping your body too rigidly planked. Think about relaxing the core and decoupling the upper and lower bodies. Let that force act to initiate body roll at the shoulders and it will increase the arch in your back slightly and temporarily. In this way it won’t be transferred to the lower body and push downward on the hips and legs.
That’s an excellent point – use the lift generated from the pull to rotate the torso rather than sink the feet.
I’ll have to work on it to smooth it out, of course. But at least that gives me a bit of understanding as to what I’m supposed to accomplish with a shallow pull.
The trick to the shallow stroke is all in the initial catch. It’s hard to explain in words, but your elbow must pop out and up as your forearm rotates down and inward. Think about how you would pull your body out of the pool when you get out after your swim… you put your hands up on the deck, and the first thing you do is try to get your elbows above your hands so that you can push down with your triceps and lats. The idea is similar here. Essentially, you try to get your elbow up so that your hand and forearm can start moving horizontally under your body. I’m sure my explanation is plenty vague, so perhaps the best I can do is point you to a video of someone who know how to swim fast:
If you search around on YouTube a bit there are other ones that slow down footage of Phelps and other swimmers so you can really get a better idea of how their bodies/arms are positioned relative to each other.
You might also consider posting a video of yourself swimming… both above and below water if possible.
Seriously, and I’m not trying to p folk off here, but anyone who starts using the pull to rotate the uper body is going to cause themselves more trouble. Rotation starts from the hips.
And here’s something that will p people off… TI is a source for bad habits.
Seriously, and I’m not trying to p folk off here, but anyone who starts using the pull to rotate the uper body is going to cause themselves more trouble. Rotation starts from the hips.
And here’s something that will p people off… TI is a source for bad habits.
I won’t take offense to being wrong and being corrected…but yes I was suggesting that it’s valid to rotate from the shoulders…I may have gotten the wrong impression but thought it was a valid approach especially for distance swimming that de-emphasizes the legs. Please offer your advice on the matter.
I think the downward component of the force vector is minimal and is neutralized with a proper positioning of the head downward. It is important to stay focused at the first phase of the catch ensuring that the elbow remains in an elevated position in relation to the hand. I think this is one of the most difficult skills to master but makes a significant difference in the power of your stroke.
Think about swinging a golf club or baseball bat. The power comes from the hips, driving the arms and hands. This will work in swimming, too. The power to drive the upper body can be derived from the hips, regardless of the kick. Use the physics and the forces to your advantage.
I think the downward component of the force vector is minimal and is neutralized with a proper positioning of the head downward
Hmmm. I’ll buy that as my arm really dives when I raise my head to breathe. (Yah, I know how to breathe with proper head position, body rotation, blah, blah, blah…) But, even without changing my existing stroke, I notice that I catch shallower when (1) I’m not breathing during that reach, and (2) when I’m putting down more power.
I can see the theoretical hydrodynamic benefit of a shallow catch in reducing the frontal area of your arm before the catch, as well as producing a lightly longer “hull length”. But, I wonder if these advantages are negated by the increase in frontal area that results from lower hips and feet. These issues seem to me to be independent of the improved power possible with a “proper” catch.
I guess the key is to learn to achieve good body position and shallow catch at the same time. Back to the pool I go. More practice needed.
My other comment would be (this will be hard for you as an engineer) - stop THINKING about it and feel it. Kinesthesis is going to help you more than thinking about vectors and angles will when you’re actually in the water.
Play around with the catch, the pull, how many beats to a kick, body rotation - you will get a sense for feeling what “works” and what doesn’t.
One of the guys I swim with, a sprint freestylist and club team coach, has a fantastic understanding of the biomechanics of swimming and I always wish, when he is trying to fix something in my stroke, I had a tape recorder so I could catch all the little bits and pieces of the biomechanics he’s describing. I am not at the point yet to understand it all and think through it and analyze like he can - but I can feel something wrong in a stroke and figure out how to tweak it, most of the time.
