Applies to all strokes
Your arms are not meant to propel your body. We, all human beings, are just not built that way.* Your core muscles — lower stomach and lower back muscles, butt, and upper thighs — are designed to propel your body, so engage your core. Swim using the same large muscles you walk and run with or, put another way, swim from your core outward, from the center of your body outward.
This is how advanced swimmers swim and there is no reason you can't swim the same way. It's not hard to do, if, and this is a big "if", you have good balance, posture, and alignment.
*Chimpanzees, apes, and other higher primates, on the other hand, do have arms designed to propel their bodies, they can swing through the jungle canopy using arm strength alone and most of their walking is done on all four limbs. Their upper body is at least twice as strong as humans, by some accounts five to eight times stronger.
Appreciate that human beings are land walkers, not tree climbers, and have a land walkers' physique. That means (if you are a human being) your strength is not in your extremities, it's in the center of your body.
Applies to all strokes