I'm a very infrequent poster on this board because of being somewhat yellow book phobic (any edition). Please bear with me and comment about resistance training for golf related movements to increase your speed. ( thus length)
Bands work, weights work, dynamic balancing using a swiss ball works it just depends on your level of fitness and what you're trying to accomplish.
I like to use the big ball instead of a bench for weight training because it forces your to maintain your balance and uses a lot of stabilizing muscles and core muscles.
Hope this helps.
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Golf can never be considered an enigma. ~HK