Is it best to run with closed fists or open hands?
This is actually a great debate because everyone’s technique is different.
The most important thing to consider is to R-E-L-A-X (famous quote from Aaron Rodgers for all you football fans). Relaxation is key to running technique. When you are tense, your muscles are tense - and tense muscles just don't work as efficiently.
It's always interesting to watch the facial expressions of runners or sprinters. If they are gritting their teeth, they are tense. If they are doing a good job of keeping things loose, you should see their cheeks bounce up and down.
So, my best answer to the question is do whatever feels relaxed. That said, usually a tight, clenched fist is not a relaxed position, and how you have your hand positioned will affect your wrist, forearm, shoulder and postural muscles of the upper back (rhomboids, traps, levator scapulae).
In general, I suggest an open hand and letting those fingers “flop” around naturally. A common cue is to imagine holding a potato chip with your index finger and thumb, trying not to break it. The feeling of relaxation will be different from person to person. Find what works for you, keeping in mind how the rest of your body feels as well.
Tony Muyco, NSCA, CSCS
Director of Training