Playing golf is not enough to improve your aerobic fitness. Having an improved level of cardiovascular fitness will enable you to maintain your energy levels, fight fatigue, and stay mentally focused for 18 holes. Walking, biking, stair-stepping, and running are great examples of cardiovascular exercise. Being aerobically fit will increase your confidence, which is what golf is all about. Functional flexibility is a very important component to improving your golf swing.
Flexibility is the range of motion around a specific joint.
If you have decreased range of motion in any joint, especially the shoulders, hips or low back, your swing may not be mechanically sound or efficient. Realizing your personal limitations is a good starting point to improving flexibility and golf performance. Just swinging a golf club a couples of times before you play is not enough to improve your flexibility. The aging process causes loss of elasticity in tendons and ligaments as well as muscle. Remember to always warm up for approximately 5-10 minutes prior to stretching.