Drills isolate the problem, help correct the problem, help ingrain the correction.
Drills are a useful part of working on form and technique in your swim. By stepping away from just swimming up and down the pool, you can focus on elements of your stroke and add the correct movement and control. You then give your speed the chance to improve through making elements of your stroke stronger.
Many novice swimmers who are just starting to swim can only manage a few lengths without taking a break. To improve your swimming by just continuing to do 500 metre sets may get you faster over time but will always be limited by inefficient form, also ingraining bad habits which will prevent you from getting faster and more efficient.
BUT drills and swim aids are only a tool and should be used properly and specifically. They are not to be used over mindless laps, use them with purpose to improve form and help with speed and fitness. Make sure you know why you are doing that drill and what it is aiming to improve.
Drills build awareness of what your body is doing and how important different elements of your stroke affect your overall body alignment, strength and efficiency.
Below is an example of the Fingertip Drag drill / Zip drill – Swim normal Freestyle dragging fingertips along the surface of water on the recovery. Focus on a high elbow recovery, which ensures proper hand and elbow position at your hand entry. You should also check your body position during this drill, focusing on good side-to-side rotation.
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