Personal trainers use contrast training when a client is keen to not only improve their strength and hypertrophy but also to add muscle and improve their physique.
As with complex training, contrast training uses the mechanism of Post-Activation Potentiation but for a different stimulus and goal. While complex training comprises a strength exercise followed by a power exercise, contrast training involves a strength exercise followed by the same exercise at a different intensity.
A typical contrast training routine
A fitness instructor devising a contrast training routine would start by asking the client to carry out one rep max (1RM), for example one rep on a bench press, working at +95% of their maximal effort. This would be followed by a rest period of anything from one to three minutes, depending on the client’s fitness levels and their ability to recover. If the rest is too short, the client will still be fatigued; if it’s too long they will lose the stimulus effect of the 1RM.
Following the rest, the personal trainer would ask the client to return to the same exercise, in this case the bench press, and reduce the weight to their 10 rep max weight, usually around 70% of maximal effort. Since the client has already fired up their nervous system with the one heavier rep, their body will be tricked into expecting a heavier weight and will find it easier to carry out the 10 reps resulting in them being able to perform more reps at a given intensity- 12 for example.
This means their training can be increased from, say, three sets of 10 reps to three sets of 12 reps. The added reps will put more tension through their muscles for longer, giving them a stimulus to adapt to that they wouldn’t previously have been able to achieve.
This exercise can be repeated for two to four sets, with a rest period of around three minutes between each set. Any more than this, the client may struggle to complete the initial one rep maximal effort bench press.
Precautions of contrast training
A fitness instructor should be aware of the intensity of this form of training: carrying out a one rep max on any exercise can be dangerous, but especially with complex movements such as a squat or a deadlift.
An alternative might be a five rep max on the same exercise with a lower weight, or to change the exercise, for example a five rep max on a leg press, followed by a rest and then 15 reps on a lower weight rather than 10 on a higher weight. This way, the client will still get the same response from the nervous system but with less risk.
Contrast training with compound exercises
This training method is generally used for compound exercises, which are multi-joint, multi-muscle exercises. This could include a bench press, a lat pull down, a bent over row or a squat, but not a simple exercise like a bicep curl. Because contrast training is a strength-based, high-intensity exercise, it’s important to use as many muscle groups as possible in order to use as much of the nervous system as possible and develop strength.
How to decide on the order of the exercise programme
Within an exercise programme, the personal trainer would start by working the client’s largest muscle groups first. If a training programme begins by working individual muscles, they risk becoming fatigued before they are needed for the compound exercise.
The programme would depend on the client’s goals, but a typical contrast training full-body routine might be:
Back squat – working on the legs but recruiting the whole of a client’s body from the neck down.
Bent over row – again, using the legs, back and muscles in the trunk.
Chest exercise –a chest exercise lying down is a good way to complete the routine as the client may be getting fatigued and this will use fewer muscles.
Alternatively, the fitness instructor could lead the client through a split session, where they work the legs on Monday, the back on Wednesday and the chest on Friday. In each case, the personal trainer should start with contrast training before moving their client on to their regular training, as otherwise they may be too fatigued to carry out the exercise successfully.