Since it's much more difficult to run after cycling, run first before heading out on your bike. Spin easily as opposed to grinding the big gears. Be sure your seat height and pedals are properly positioned. Finally, always wear a helmet and leave the music headphones at home. Swimming Swimming is one of the best cross-training activities for several reasons.
Swimming enables one to build muscular strength and endurance while improving flexibility.
It is especially recommended for those who want to prevent injury, are pregnant, are recovering from an injury, are suffering from joint or bone conditions, or are overweight and want to exercise in a weightless environment. For the compulsive runner who has a hard time taking a rest day, swimming gives those fatigued leg muscles a breather while at the same time, provides an excellent upper body workout. Additionally, water is considered a healing medium, providing a therapeutic effect for all muscle groups. While gentle kicking alleviates some muscle soreness and fatigue, avoid using the kickboard for hard kick sets on your running rest day. Nevertheless, what truly counts is that the heart, lungs, and muscles are still processing oxygen.