Here are some guidelines for how to use drills more effectively…
Practice precision; never practice struggle.
What is practiced is what will be perfected. When you reach a point in the drill where you are failing to achieve the focus point it is time to stop, rest, and start again, or move to a new focus point.
Keep a single focus point on every length.
Only add or combine focus points when one of them becomes ‘easy’ (meaning, it requires less effort to focus on and maintain) and you are ready to increase the challenge level a little. You may have several focus points you want to work on today, but at any one time just focus on one of them.
Make small, gradual increases in difficulty and distance.
Only make increases up to the point that you can hold good form. When form deteriates, step back and work towards that limit again. Pushing up to the limit is more effective than pushing over it.
Use fewer sets of higher quality.
Smaller, higher quality sets are more productive than big sets that cause your focus and quality to deteriate and begin to practice struggle. Do short segments of practice on each focus point, either spending a few minutes on one, then switch to a new one, or cycle through several within the set.
Minimize kicking.
Use minimal kicking in the beginning stages of doing drills to make sure Balance is being improved, not avoided. The goal is not to finish the length, or get the set done, but to execute the movement as intended. We are perfecting our ability to control our movements, not get to the other side.
Stop to breathe.
Until breathing skills are well developed, practice skills between breathes then stop, and start again. Once interrupted or integrated breathing skills are developed, use them to do full pool-length drills.
Slow it down.
Practice precision before speed, and speed will follow. Neuro-muscular control is first developed in slow, careful movements. As precise movement is practiced frequently and consistently the nervous system will build up the circuits supporting it so that the movement will become easier, faster, and more powerful.
Ease and speed in the water will come from a body that is well-trained to cut through it with fluid precision movements. The neuro-muscular foundation for high speed is first built in slow work. This means giving yourself sufficient rest intervals during drill work so that you will be able to keep pushing your neuro-muscular limits without being pre-maturally fatigued by muscular and metabolic exhaustion within the practice time. There is time for the latter kind of work once you establish some level of stroke control. The power appropriate to your goal will be developed as your quickening neuro-muscular system draws you into more intense challenges. In other words, keep your heart rate in the aerobic range while building technique.