It is well recognized that progressive resistance training can lead to muscle hypertrophy. This has traditionally been linked primarily to mechanical stress. It has also been established that different programs lead to different degrees of hypertrophic gains. Thus, recognizing the mechanisms that will maximize hypertrophy is of upmost importance to strength and conditioning professional.
It has been proposed that there are three primary mechanisms that lead to muscular hypertrophy. These mechanisms are mechanical tension, muscular damage, and metabolic stress. Mechanical tension can be varied by altering the external torque. This can be accomplished through exercises that provide high external torque when the muscle is at a long length. This type of exercise has been linked to the highest amounts of delayed onset muscle soreness, most likely due to the stretching of sarcomeres and subsequent muscular damage. Furthermore, long length exercises may provide an enhanced stimulus for passive tissue remodeling, which have athletic or rehabilitation implications as elastic strength is an important aspect of decreasing injury. In contrast, certain exercises allow for peak torque to occur at shorter muscle lengths. These exercises may be superior at creating metabolic stress through increased hypoxia and build-up of metabolites, both of which have been shown to be important in enhancing muscular hypertrophy.
In order to maximize hypertrophy, the length-tension relationships of muscles and various exercises should be considered during programming. It has been shown that at least three exercises per muscle group results in superior hypertrophic adaptations. Anecdotally, at least two exercises should be used that work the muscle in a lengthened position. This will help to maximize muscle tension and resultant muscular damage. Additionally, at least one exercise that trains the muscle in a medium to short length should be used to create metabolic fatigue and enhance the hypertrophic adaptations. Lastly, joint angle should be considered, as this is important for developing strength through an entire range of motion.
David Larson graduated magna cum laude with a Bachelors of Science degree in Kinesiology from Arizona State University and is a Certified Strength and Conditioning Specialist through the National Strength and Conditioning Association. David is also currently pursuing a Masters of Science in HumanMovement, specializing in both Sports Conditioning and Geriatric Exercise Science. David has played soccer since he was five and continues to play the game competitively today. David loves when his clients tell him how much their lives have been and are improving through fitness.
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