I was reading on this website power tidbits page regarding impaired power development during the eccentric and concentric phase, that to develop strength and muscle, it's better to power lift. I was taught by a triainer to lift in a 3-1-3 ratio, that is, lift for three seconds, hold for one second, then lower for three seconds.His reasoning is the muscle/muscles can lengthen better and build up better when lifting in this manner, not to mention less chance of injury by lifting slow. I am interested in comments on which is a better method to build and strengthen muscles.
Strength has many faces. Strength is often referred to as force. To lift an 100 lb object, you need to produce more than 100 lbs of force, strength.
If the most you can lift is 100 lbs (your 1RM--1 repetition max), this is you Limit Strength.
Power is Force X Distance/Time (Distance Divided by Time). "Since the terms force and strength are often used interchangeably and distance divided by time is the same thing as speed, power can more simply be defined as strength multiplied by speed. Therefore,
Strength x Speed = POWER." http://www.strengthcats.com/plyobenchpress.htm
Speed is simply how fast you can go. Like limit strength it is fairly easy to understand. A car that can go 60 miles in a hour is traveling at a speed of 60 miles per hour.
Lifting heavy loads will increased your limit strength. Slow movements such as your "3-1-3 ratio" minimize momentum. With no momentum, the muscle has to works harder and your strength inceases. That providing that you tax the muscles involved with heavy loads, 85% plus of 1RM. Low reps (1-5), high sets (8 set plus) and 3 minutes rest periods increase Limit Strength.
If you you max lift is 100 lbs, then you'd want to train with 85 lbs or more.
The foundation of power and speed are built on strength. Thus, a novice will increase their power and speed, initially by increasing their strength.
However, as Stephen Johnson noted in his post, doing nothing but lifting heavy weights all the time will make you stronger but at you will become slower.
At some point, to increase your power you need to incorporate moderate loads in which drive them up with a great deal of speed.
Loads of between about 48-62% of 1 RM are recommended as a means of increasing your power in most exercises. Reseach: DANIEL BAKER, STEVEN NANCE and MICHAEL MOORE. 2001: The Load That Maximizes the Average Mechanical Power Output During Jump Squats in Power-Trained Athletes. The Journal of Strength and Conditioning Research: Vol. 15, No. 1, pp. 92–97.
Again, if your 1RM is 100 lbs, to develop power you would want to train with 48 lbs to 62 lbs for about 1-3 reps per set.
Power movements should be kept to about the same number of sets and reps as Limit Strength sets, 1-5 reps, 8 set plus, with rest sets of 3 minutes or longer.
The difference between training for Limit Strength and Power is your training percentage. Let me reiterate, for Power the load need to be between 48-60% of your 1RM and with Limit Strength training your load need to be 85% or higher of your 1RM.
In your power movement, you need to get some type of bounce out of the hole. This elicits/develops the stretch reflex.
The stretch reflex in the body acts like rubber bands. When stretched quickly the muscles stretch back faster, producing more power. Research show you can produce up to 18% more power when you use the stretch reflex.
As an example let take a standing jump. When you bob down before jumping, you elicit the stretch reflex. Doing so propels you higher/further than if you had justed from a static/dead stop position.
The same thing works in your weight training. You want to get some type of bounce out of the hole of a squat, bounce off the chest in a bench press, etc.
To maximize your strength, you want to employ limit strength, power and speed movements at some point in your training.