Muscles Used in the Backstroke. Even though you're swimming on your back, you use your abdominals in addition to the muscles of your back -- the latissimus dorsi and spinus erectors -- to support you as you flow through the water during the backstroke.
The average distance for a pitching wedge is 130 to 135 yards; for a sand wedge 115 to 120 yards; and for lob wedges 75 to 95 yards.
1 Mandatory: 2 umpires (certified if possible) for all games (upper and lower levels). Umpires must be in appropriate attire. 2  Pitching distance is at 43 feet.  Most double headers are at 5:30 & 7pm, but some cities can only play them at 7 & 8:30pm so please pay attention to this on the schedule.