The main points I stress to individuals for swimming:
1. Don't cross the midline of your body. This is from straight above the head where your hand enters all the way down your body. Once the midline swimming is understood, then you work on rotating from the "barge" to the "speedboat" with help from rotating the hip.
2. High elbow recovery. This helps the body be streamlined moving forward. A lack of high elbows has a tendency to throw the hips side to side, crossing the midline, that causes the body to wiggle through the water. A lack of high elbows also causes the muscles of the arm to be contracted during recovery and not able to relax. When entering, have the fingers enter the water first, followed by the wrist and then elbow.
3. Get rid of the S shaped sculling motion upon entering the water. This wastes time. Enter the water and start to pull, thinking about the area between your fingers and the elbow as a wrought iron bar that doesn't bend. Keeping your elbow bent at approximately 90-110 degrees prevents the arm from crossing the midline and gives you the best power of pushing through the water (which is 1100 times more dense than air).
4. Short, little kicks. Too much bending at the knee causes a braking motion. Your kick should really be within an 8-14 inch range from all the way up to all the way down. Kicking may only be 20-30% of the propulsion forward, but training your kick can make it have better economy to your energy system.
5. Head position. There is no set place to put it. Rather, it depends on the individual. Too high and the butt may sink. Too low and the head is more like an anchor in the water.
Here are a few swimming drills I use at my triathlon camps and swimming clinics for people to improve their swimming as well as their open water swimming.
**** It is important to over-exaggerate any changes in your swimming stroke in order to change your form to a better and more efficient technique. This feeling can take anywhere from a few weeks to months, depending on how often you swim and how disciplined you are with accepting changes. It would be best to have someone knowledgeable about swimming observe you and offer things to change. In addition, being filmed above and below water will give you a visual of things you need to change and allow you to archive your swimming to view it later when periodically filmed***
PS. 90% of the time, drills are slow. Don't hurry the drill and not make the best use of your time.
1. If you cross your midline upon entry, swim like a penguin with your arms feeling FAR apart from the midline. Visualize the appendages of a penguin as the fins are more to the side of the body. Swim like that where you "feel" like your hands are entering the water way out to the side of your body. In reality, you may be entering right by your midlline!
2. To help not cross the midline under the body, try to breathe as little as possible for a 25 or 50, drop the chin to the chest and watch to see if the hands are crossing the midline near your chest and belly. If they are, then make the angle of your elbow larger.