Today’s discussion of conditioning the athlete revolves around the principle of overload and why it’s necessary to improve fitness.
The principle of overload states that a greater than normal stress or load on the body is required for an adaptation to training to take place. How much load is required depends on the individual and the type of training that is being undertaken.
For an endurance athlete, I use the very general equation that states:
“Fitness =- Frequency x Intensity x Time”
That is, fitness (in the endurance sense) is related to how often you train, the intensity at which you train at and the duration of training. These variables can be manipulated independently or concurrently and the effect is not always multiplied in kind when you to try increase all three at once!
The adaptations that occur as a result of endurance training include increased mitochondrial and respiratory capacity of muscle fibres – in layman’s terms – oxygen is able to be taken up and used more efficiently as a result of increased fitness. Coupled with more reliance on the oxidation of fat and less reliance on muscle glycogen (thus using fat as fuel, more than stored carbohydrate) it allows us to perform more strenuous exercise for longer periods of time without the risk of running out of fuel (aka bonking).
With strength training, overload is achieved through both volume – number of repetitions lifted and intensity – actual amount of weight lifted per repetition. A well written strength training program will manipulate both of these factors as well as examine the total amount of weight lifted per training session.
In strength training, muscular adaptation occurs as a result of progressive overload and is dependent on the muscle fibre types that are present within the body. The distribution of these is genetically determined and it has been found that those who have a higher percentage of Type 2 (or fast twitch) fibres, typically gain strength faster than their counterparts who possess more Type 1 (or slow twitch) muscle fibres. A muscle that is strengthened will respond by increasing in size (hypertrophy) and density (the theory being that muscle fibres tear during intense exercise – this is known as microtrauma).
“Often strength is indexed using a 1RM (one repetition max) test. “
This can be estimated using a number of different formulae. I checked a “Journal of Strength and Conditioning” article on this and counted about 12 different equations, thus for accurate comparisons – pick one and stick with it.
In both endurance and strength scenarios applying overload should be a measured effort, taking into account how the athlete recovers. Good nutrition practices also have a big impact on both recovery and improved performance, both in the gym and in life. In improving flexibility and mobility, slow progressive effort seems to work best.
For best results the principle of overload shouldn’t be applied to every training session. Training loads in both the endurance and strength sense should be varied weekly and training sessions that allow more recovery should be also encouraged.
When I teach my own group fitness classes, which I choreograph myself, not every class includes maximal effort. The “Three Jerseys” rides which I taught to coincide with this year’s Tour De France each had different components of overload. These were taught over the last three weeks and each focused on adaptation or overload in a slightly different way.
- “Polka Dot Jersey Ride” – included five hill climbs of varying grades and intensities with the focus of the class being on development of leg/core strength and endurance
- “Green Jersey Ride” – included three varied speedwork tracks including efforts of pure anaerobic work with long recovery in between – focus on developing explosive speed, anaerobic/lactate tolerance. Few hills.
- “Yellow Jersey Ride” – included a mix of hills and time trial work – no pure speed – the focus being on intense aerobic effort and the duration was made longer to reflect this.
With the strength training I am currently undertaking, my focus is on strength, mobility and functional movement. Thus you’ll see plenty of exercise that taxes the entire body with each rep and plenty of time to recover in between bouts of work.
How do you know when you’ve got the principle of overload right? Without using any numbers or measures, what you’ll notice is progression that is injury free and fills you with plenty of energy. If you’re overdoing it, you’ll be tired, lacklustre and unable to produce the same effort.
How do you use the principle of overload? Have you ever taken your training too far and paid the price?