Elite and recreational athletes, bodybuilders, personal trainers and regular gym-goers should all use hypertrophy as part of their training toolkit.
The physiological adaptation that results from hypertrophy training can change both an individual’s appearance and their performance.
What is hypertrophy training?
Simply put, hypertrophy training is a way of encouraging muscle growth with the aim of increasing bulk and/or power and strength. However, not all muscle gains will result in increased strength, and improved strength does not necessarily result in bulking up – it all depends on training techniques and the stimulus put upon the body.
Muscle growth is stimulated by mechanical stress on muscle tissues.
What are typical hypertrophy training exercises?
Fitness instructors will often work with clients who want to increase muscle size and/or strength. The resistance training programmes they devise to achieve this may include any of the following:
• Bench press
• Front/Back barbell squat
• Leg Press
• Lat pull down
• Pull Ups
• Shoulder press
• Bent over rows
What variables will affect the training results?
While various factors can affect the success of hypertrophy training between one individual and another – from age to genetics to diet – various training techniques will also see different results.
Type of training
Eccentric (lengthening) muscle contractions are believed to optimise muscle hypertrophy more than isometric or concentric actions- they also are the strongest muscle contraction. However, concentric failure is also an important stimulus to place upon the muscle to optimise hypertrophy.
Time under tension (TUT)
Is the speed in which you perform the exercise. If you perform your reps quickly (eg. 10 reps in 10 seconds) there would not be the same stimulus of performing your reps slower (eg. 10 reps in 70 seconds).
Current American College of Sports Medicine (ACSM) guidelines for hypertrophy are that you perform 3-4 sets of 10-12 reps at a tempo of 4:2:1 (eccentric:isometric:concentric)
Frequency of training
Hypertrophy sessions are generally ‘split sessions’. This means you train a specific group or groups of muscle in one session eg. Chest and Triceps on Monday, Legs on Wednesday, Back and Biceps on Friday.
There are many variations of split routines that you can follow that will change the stimulus on your body and therefore, hopefully, your body’s adaptation. The key is to find a frequency and structure that suits your clients lifestyle, time availability, level of fitness and experience.
Intensity of training, reps and sets
The intensity of the exercise and amount of explosive force used are particularly relevant as they will determine the mechanical stress placed on the muscle.
An exercise carried out at low intensity will recruit Type I motor units, while a high-intensity routine will recruit more Type IIa motor units. An exercise performed at moderate intensity for a moderate amount of time will recruit Type IIa fibres.
Typically, a bodybuilder will have more Type IIa muscle fibres and a weight lifter (powerlifter and Olympic Weight Lifter) will have more Type IIb.
Hypertrophy training generally occurs between 6-12 reps. As a beginner lifting any amount of weight for any amount of reps will generally increase muscle mass. But as your body becomes accustomed to the weight you will need to be more specific with your intensities and the stimulus you put upon the muscle.
ACSM’s guidelines are:
Intensity- use a load of 70-85% 1RM for novice to intermediate clients and a load of 70-100% for advanced clients.
Sets- 1-3 sets of 8-12 repetitions for novice to intermediate and 3-6 sets of 1-12 repetitions for advanced clients.
Rest period- 2-3 min for higher intense exercises that use heavier loads. 1-2 minutes between the lower intense exercises with light loads.
Sequence of exercises
An exercise programme should start with a series of compound exercises. Compound exercises are multi-joint, multi-muscle exercises eg. Squats, deadlift, bench press and pull ups. Once the heaby lifting has been completed you can finish a session with a series of isolation exercise eg. Leg extensions, straight arm pull down, dumbbell flyes and bicep curls.
What’s the difference between functional and non-functional hypertrophy?
Functional training (see our blog on Functional training – a new tool for fitness professionals) is designed to make it easier to carry out everyday activities by replicating their movements. An example might be weight training that replicates the movement of lifting a heavy box.
When it comes to competing athletes, functional hypertrophy training helps them to better perform in their specific sport. However, some competitors, such as bodybuilders, will be aiming to bulk up without specific functional activities in mind.
If you have particular goals and are unsure of how to reach them, a professional personal trainer or fitness instructor should be able to advise you on the best hypertrophy training regime for your needs.