Transfer of Training Part 3 - Which Types of Muscle Contractions to Train?

In the past 2 weeks we've covered the different types of muscle contractions and also how they look when put into action in your training.

I like to divvy up performance training into 5 categories being:

1. Stiffness of the Lower Leg/Foot Complex
2. Relax/Contraction Speed
3. Force Absorption
4. Overspeed
5. Force Output

Stiffness refers to the ability of your lower leg to absorb the forces being placed though with minimal muscle deformity, or as world class sprint coach Frans Bosch calls "muscle slack". Think of a sprinter in the blocks. When the guns goes off he must push back into the blocks through his lower body and then propel himself off them to get moving. 

You can see at about the 18sec mark where his lower body shifts ever so slightly to get the leverage to come out of the blocks. Asafa Powell is an ex-fastest man in the world so he has minimal muscle slack but if you ere to watch us do this, there would be a lot more time between us pushing into the blocks and actually coming out of them.

Stiffness is also a factor at max velocity pace as the less deformity you go through the better bounce you get with each step. Think of a flat footy coming off your boot where it would "sag' once it hits your foot versus a freshly pumped up ball that rebounds straight off your foot as soon  as you make contact with it.

Look at Bolt's foot upon impact - his heels stays well off the track and he pretty bounce bounces off the track with each step where us normals would collapse through the feet where our heels touch the track and our knees would buckle from not being able to handle the eccentric load of ground contact.

Relax/Contraction Speed refers to the ability of your muscles to contract then relax then contract again which is what happens with each muscle contraction. It also entails how much you can relax with each contraction too.

Right now tense your upper arm and try and curl as fast as you.

Go I'll wait.....

Now relax the arm and try and curl as fast as you can.

Waiting...

I bet you had a much faster curling speed with the relaxed arm.

You cannot be fast when you are tense. Heavy weights builds tension. Heavy weights might not be the holy grail of speed they're made out to be. Tension while trying to perform high speed activity also results in muscle strains and tears. You've got to be able to build tension but you've also got to be able to release it.

Overspeed refers to using methods that have you perform at a very slightly higher velocity you cannot reach on your own. This is used to train the nervous system to do its job faster (faster contraction rate, produce high force faster etc). It can be done both eccentrically and concentrically to overload specific portions of movement.

Force Absorption is what you must be able to do when landing from any height at all. You might not gain much height through sprinting but with the max velocity component you can be landing with 5 - 6 x your own body weight on a single leg with each contact when you're at top speed. If you can absorb great force then you'll be able to put out great force which leads me to...

Force Output is pretty much a product of all of the above and is really the end result that we're looking to improve.