One of the hardest questions to answer when it comes to strength training is How much rest does one need between sessions to maximise chances of positive adaptation such as muscle growth? Over the past six months I’ve written quite a few articles on the basics such as training variables and guidelines, progressive overload, the body’s energy systems, and recovery methods. All of these articles give you pointers on how one should approach strength training to give yourselves the best chance of achieving results.
The short answer to the question above however is that everybody is different therefore there is no definitive method. So where do I go from here, well I thought I would just go over a few basic ingredients that are required to give you the best chance to achieve your goal of muscle gain and the added strength that comes with it, and once we’ve done that have a look at how rest can enhance your efforts.
Correct Posture, Form
The first is that you need to make sure that you are performing all given exercises with the correct posture and form otherwise not only will you heighten your risk of injury you will also negate any real gains in the muscle group you are trying to work. The classic example of this in the gym environment is someone doing arm curls and swinging back with the barbell or dumbbells. There is a train of thought however that sometimes cheating on your form to lift a heavier weight is acceptable, whilst this may place more force on the target muscle and hence the recruitment of more muscle fibre this is not something I adhere to or would recommend purely for the high risk of injury.
Muscle Actions
The muscle actions themselves are also important, that is you should be training not only the concentric muscle action that is when the muscle is contracting,(pushing the weight up on the bench press) you should also train the eccentric muscle action, when the muscle is lengthening, (lowering the weight down to your chest in the bench press). Whilst this is a topic that should be covered on its own suffice to say here that you should also pay attention to the eccentric muscle action by lowering the weight down in all exercises you do, in a controlled and smooth movement.
Exercise Intensity and Volume
Another important consideration is that you progressively increase the weight in your lifts. For muscle growth (hypertrophy) it is commonly held that you need to perform between 8-12 reps at a moderate to heavy weight that is 70-85% of your one repetition maximum commonly known as 1RM. As an example if your IRM is 60 kg on the back squat you would do the number of reps mentioned above at a weight between 42 kg to 51kg. I tend to use 10 reps as the marker for this, so when you can comfortably lift the weight you are on for 10 reps then its time to move up to the next increment. Remember that the more muscle fibre recruited in the lifting the more there is to repair, which given the right conditions will make the muscle bigger and stronger.
Once you have completed a 6-8 week phase of hypertrophy training, move into a strength phase. Do the same exercises however this time lift heavier with fewer reps 85% upwards of your one repetition maximum, let’s take the same example as above the back squat, your maximum for 1 repetition is 60 kg then you should do 51 kg lifts for 6 reps and so forth.
Motor Unit Recruitment
Let me return to the muscle fibre recruitment I mentioned briefly above, without going into to much technical jargon, each muscle has a different number of muscle fibres and motor units, the so called low threshold or smaller motor units are recruited first followed by the high threshold motor units. A motor unit is simply a bundle of muscle fibres. The difference being that the smaller motor units only need low electrical stimulus for activation whilst the higher threshold as the name implies need more stimulus for activation. To complicate matters a little more there are two types of muscle fibres, smaller motor units have predominantly Type 1 (also known as slow twitch fibres) whereas the higher threshold motor units have predominantly Type 2 (also known as fast twitch) fibres. Now that I have confused you let me get to the point, in resistance exercise it is the load, (amount of weight lifted) that determines how many motor units are recruited. Heavier loads recruit more motor units than lighter loads, and for muscle growth the more muscle fibre recruited the better, therefore the need for heavier weights and less repetitions as explained in the strength phase above.
Rest between Exercises
The rest period between each exercise varies according to your goal if it is muscle size gain (hypertrophy) studies have shown (Kreamer et al. 1991) for moderate to high intensity lifts with volume as described above 1-2 minutes rest results in greater acute metabolic responses of anabolic hormones than programs using longer rest periods of 3 minutes. What this means according to the mentioned studies, is that the shorter the rest the greater the metabolic stress (higher levels of lactic acid in the blood) which in turn is the trigger for hormone release, naturally occurring anabolic hormones stimulate muscle protein synthesis leading to increased muscle size.
Anabolic versus Catabolic
Wow this is getting a little out of control as far as my stated promise of not getting too technical on you, but now that I’ve come this far I’ll need to keep going. Let me briefly explain the terms anabolic, and catabolic. In simple terms anabolic is when there is synthesis in a cell and the storage of energy and catabolic is when there is a breakdown in a cell with the release of energy. To make it even easier to understand anabolic is when your muscles (body) are getting bigger and catabolic is when you are getting smaller. Obviously we want to maintain an anabolic state, this can be achieved by eating a good balance of the bodies nutrients, protein, carbohydrates and fats so that the body has the energy and necessary tools to repair the damage done to the muscles fibres, in turn keeping you growing.
The other important consideration to keep you anabolic is rest. Now we’re getting somewhere close to my opening question, to keep on growing you need enough rest between workouts moreover between muscle groups. Muscle growth doesn’t occur in the gym or at your outdoors training venue when you are training it takes place when you are resting between sessions. As I said earlier the period of rest will vary between individual but there is one golden rule that you should adhere too and that is don’t train a muscle group if it is still sore from the last workout, it will be couterproductive.
On the other side of the equation if you eat poorly and overtrain you run the high risk of putting yourself in a catabolic state, where your body will start using your hard earned muscle for energy. Why muscle and not fat? This may surprise some but muscle is easier to burn and if your body is in a catabolic state then it will start using your muscle to get the energy it needs resulting in your muscles getting smaller.
So to summarise whilst I’ve only scratched the surface with most of the topics discussed above, the basics to give yourself the best chance of achieving your goal of muscle growth and the accompanying strength gain are as follows: make sure you perform the exercises with good form, use both the concentric and eccentric muscle actions, vary the intensity and volume of your lifts, rest between exercises according to your goal, eat well and as the old cliche goes last but not least get adequate rest between sessions for each muscle group.
Wishing you all a very Merry Christmas and a Happy and Joyous New Year for 2012.
Zol
Fitness Moves