One area of debate that relates to sports training is whether or not resistance training is beneficial for endurance athletes. Those that oppose this type of training, of course, say that it is not beneficial and that the time spent resistance training would have been better spent doing sports-specific workouts. Being a proponent of weight training as a means to increase performance, I look at it like this: the stronger that I am, the more capable I am to perform and compete at my best. Therefore, I believe that all athletes can benefit from a well designed and well executed strength training plan.
It is well documented that resistance training helps to strengthen the tendons, ligaments, and stabilizer muscles involved in the sport-specific movements that are used in endurance training. Some of those stabilizer muscles are those found in the knees, back, neck, ankles and most importantly the core. Running and cycling put a lot of strain on joints, and they endure a tremendous amount of pounding during training. By working to strengthen all areas of the body (again those ligaments, tendons, etc.), the body will be more capable of absorbing the punishment placed on it during mile after mile of endurance training, while at the same time helping to reduce the risk of injury.
Weight and resistance training also builds muscle, which in turn has a positive effect of our basal metabolic rates (the amount of energy used to sustain life while at rest), meaning that our bodies will become more efficient at burning calories and stored fats. This translates into an increased potential for fat loss; therefore weight training assists us in maintaining a lower body fat percentage, which also helps improve endurance performance.  There is still that fear that weight training produces bulk, which will in turn slow endurance athletes down. Unless you are planning on adopting weight training and nutrition plans designed to gain large amounts of muscle mass, you have nothing to worry about in terms of gaining too much muscle! Any gains in muscle resulting from a weight training plan designed for increased endurance performance will certainly present an athlete with more benefits and performance gains than limitations resulting from the potential for a small amount of weight gain. Remember that athletes that have overly muscular physiques are training and eating in a manner to produce those types of results.
By balancing endurance and resistance training, your physique will also be balanced. Fast-twitch and slow-twitch muscle fibers are both utilized during swimming, biking and running, therefore it is important to work towards improving the strength and efficiency of both muscle fiber types. The way I see it is I want to create the best possible environment I can for my muscles and work become strong, while at the same time doing what I can to perform my best. By having a well rounded training program that includes all my endurance workouts, with a healthy dose of strength and flexibility training thrown in, I feel that I am giving my body the exercise it needs to perform optimally.
Before beginning any type of exercise program, it is important to check with a licensed healthcare provider to make certain that you are not at risk of injury or illness. It is also important to consider locating a certified fitness instructor in your area in order to help you with designing a strength program that is individualized to you fitness level, needs and personal goals.
