I voted… but im torn on Track, Soccer and Swimming as the 3rd! Soccer is tremendous footwork and cardio, Track is a bit cardio and lots of conditioning and lifting, Swimming is amazing cardio and resistance training. Of those 3 I voted track but any of them IMO help a great deal. Basketball can help some with footwork and catching - maybe? Does catching a round ball translate?
Also, track is the most available sport at most schools of those 3.
I think it really depends on the football position. Offensive or defensive Lineman could really get help by being wrestlers or boxers. Learning how to use leverage / hand speed. Wrs / RBs I think it would be track. Help to Increase speed and explosiveness. DBs, probably basketball… for short area quickness and help with ball skills (wrs that can’t catch play corner… Jk)
I don’t think stamina related sports would help much. Soccer, cross country, etc. They are just so different. The body types and physical skills to be successful are drastically different. Football is about power, explosiveness, strength and change of direction. Soccer is about stamina, body control, pace, etc. a build for long distance running is the opposite of explosion. It’s consistent from, pace, stamina etc.
I said track and wrestling. I’m thinking of general benefit for a kid who is into football.
Wrestling causes you to turn into a ball of muscle with body control and track obviously helps you with footspeed and explosiveness.
I think track is important for WRs and other skill positions. So is baseball and basketball. Both those sports teach eye-hand coordination and basketball is great for developing explosiveness. Wrestling is good for guys who play on the line like nose tackles. Our high school would always have a little ball of muscle that wrestled playing NT.