While bodybuilding may still dominate many sport-specific strength training programs, in reality it is only suitable for a small number of athletes and should only make up a portion of the overall conditioning program. See the sport specific approach to strength training article to see how these sample hypertrophy weight training programs are incorporated into the annual plan.
Athletes that can benefit from a phase of hypertrophy training include shot putters, rugby players, heavyweight wrestlers and linemen in football. For these individuals, an increase in active fat-free mass is beneficial. Other athletes such as boxers and wrestlers may want to move up a weight class and can use a bodybuilding approach to do so.
Traditional bodybuilding aims to increase the size of every muscle group making it a time consuming and enervating pursuit. Hypertrophy training for sport on the other hand aims only to increase the size of the prime movers, saving time and energy for other modes of training.
Whilst these hypertrophy weight training programs increase muscle and mass, they do not result in the nervous system adaptations that occur with maximal strength training - such as increased recruitment of fast twitch fibers and better synchronization of the muscles involved in the action (1).
To this end, a phase of hypertrophy training should be followed by a phase of maximal strength training before finally being converted into sport-specific power or muscular endurance.The table below is an example of how this may occur for a collegiate-level football lineman:
is the increase of the size of an organ. It should be distinguished from hyperplasia which occurs due to cell division; hypertrophy occurs due to an increase in cell size rather than division. It is most commonly seen in muscle that has been actively stimulated, the most well-known method being exercise.
Hypertrophy is only desirable when it occurs in the skeletal muscles. This is most effectively done by undertaking resistance training, though it can also occur during other high anaerobic exercises such as interval training, rowing, cycling and sprinting.
For hypertrophy to occur in the skeletal muscles, the muscle must be directly stimulated as discussed above. Also a diet, in which there is a caloric surplus and abundant in protein is required in conjunction with regular rest (8-10 hours per night). Also you should consult with your physician before undertaking any strenuous exercise routine.
Hypertrophy can be pathological in many organs; for example in the heart hypertrophy of the left ventricle can be associated with up to a four fold risk of dying over the following 5 years. In skeletal muscle, it is usually helpful and increases strength.
Two different types of hypertrophy are common; Sarcoplasmic hypertrophy, in which sarcoplasmic fluid in the muscle cell increases rather than the contractile protein, and hence no increase in contractile strength. Myofibrillar Hypertrophy, in which there is an increase in myofibrils, and hence increase in muscular contractile strength.
Resistance training
Resistance training typically produces a combination of the two different types of hypertrophy; contraction against 80-90% of the one repetition maximum for a lower number of repetitions causes myofibrillated hypertrophy to dominate (as in powerlifters, olympic lifters and strength athletes), while several repetitions against a sub-maximal load facilitates mainly sarcoplasmic hypertrophy (professional bodybuilders and endurance athletes).
Ventricular hypertrophy
Increased ventricular mass is an adaptation by the ventricle to increased stress, such as chronically increased volume load (preload) or increased pressure load (afterload). It is a physiological response that enables the heart to adapt to increased stress; however, the response can become pathological and ultimately lead to a deterioration in function. For example, hypertrophy is a normal physiological adaptation to exercise training that enables the ventricle to enhance its pumping capacity. This type of physiologic hypertrophy is reversible and non-pathological. Chronic hypertension causes ventricular hypertrophy. This response enables the heart to maintain a normal stroke volume despite the increase in afterload. However, over time, pathological changes occur in the heart that lead to a functional degradation and heart failure.
If the precipitating stress is volume overload, the ventricle responds by adding new sarcomeres in-series with existing sarcomeres. This results in ventricular dilation while maintaining normal sarcomere lengths. The wall thickness normally increases in proportion to the increase in chamber radius. This type of hypertrophy is termed eccentric hypertrophy.
In the case of chronic pressure overload, the chamber radius may not change; however, the wall thickness greatly increases as new sarcomeres are added in-parallel to existing sarcomeres. This is termed concentric hypertrophy. This type of ventricle is capable of generating greater forces and higher pressures, while the increased wall thickness maintains normal wall stress. This type of ventricle becomes "stiff" (i.e., compliance is reduced) which can impair filling and lead to diastolic dysfunction.
Neural Response
The first measurable effect is an increase in the neural drive stimulating muscle contraction. Within just a few days, an untrained individual can achieve measurable strength gains resulting from "learning" to use the muscle.
Genetic Response
As the muscle continues to receive increased demands, the synthetic machinery is upregulated. Although all the steps are not yet clear, this upregulation appears to begin with the ubiquitous second messenger system (including phospholipases, protein kinase C, tyrosine kinase, and others). These, in turn, activate the family of immediate-early genes, including c-fos, c-jun and myc. These genes appear to dictate the contractile protein gene response.
Protein Synthesis
Finally, the message filters down to alter the pattern of protein expression. It can take as long as two months for actual hypertrophy to begin. The additional contractile proteins appear to be incorporated into existing myofibrils (the chains of sarcomeres within a muscle cell). There appears to be some limit to how large a myofibril can become: at some point, they split. These events appear to occur within each muscle fiber. That is, hypertrophy results primarily from the growth of each muscle cell, rather than an increase in the number of cells.
Penile Hypertrophy is the continual enlargement of a males penis.
Examples of sample hypertrophy:
Hypertrophy weight training programs can follow several formats. One popular format is the total body routine where each session consists of exercises to target all the major muscle groups in the body. This would be performed 2-3 days per week with at least 24 hours rest between sessions:
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