Review of Research;
Cook (2013) Three Weeks of Eccentric Training Combined with Overspeed Exercises Enhances Power and Running Speed Performance Gains in Trained Athletes. Journal of Strength and Conditioning Research, 27:1280:1286
This research (1) used experienced athletes (rugby players, approx 20 years of age, min. 2 years of structured training), and put them through a 12-week preseason training program, with 4 separate 3 week training blocks. The blocks were eccentric loading with overspeed, eccentric loading with regular speed work, traditional loading (ecc and con) with overspeed, and traditional loading with regular speed. While most of the athletes had large effect size improvements over 12 weeks, the eccentric training groups had the largest improvements in strength measures. For lower body power (in the CMJ) the eccentric with overspeed was the highest, while speed was highest in the tradidional method with overspeed training.
For ‘eccentric training’ researchers used mostly the same exercises as in the traditional loading parameters (power clean, RDL, bent-over-row, etc.) but tried to emphasize the negative or eccentric phase of the lift, while getting a spotter to return it to the start position. Overspeed referred to doing assisted countermovement jumps and sprints down a small grade to enhance jump height and running speed. Traditional speed work was similar but sprinting on flat ground and bodyweight countermovement jumps. More details of the actual training program can be seen in the methods section.
The researchers talk about eccentric-focused loading for enhancing force production since it is known that the eccentric muscle actions can withstand much greater forces. In the treatments they used in this study, the results echoed this. Power and speed are two different concepts, and should always be treated as such. We often lump them into the same category. Speed refers to unloaded movements and characterizes the absolute quality/quantity of how fast you can move. Power is a measure that combines force output and the time it takes to produce it, and is highest when there is an optimal interaction of these two metrics, not when either is at its best (Peak Force, or Max Speed). Power may be an important metric for sport performance, but when speed is the desired outcome, the training must be focused on that, rather than improving power. This is very important for Athletic Development coaches, since we are always looking for different exercises or methods of training that CORRELATE with something else. Sometimes it seems too simple to just stay with speed for a whole block if it’s a priority, but it is probably the right thing to do.
This was exhibited when you compare the eccentric loading with traditional loading when both were paired with an overspeed stimulus. Eccentric loading alone actually made most athletes slower. This was likely from the fact that the resistance training component was performed at a much slower rate of movement. Adding overspeed elements negated this loss in speed and resulted in a small increase in speed over the 3 week block. With traditional loading there was an increase in speed without the overspeed component (small), and the largest improvement came with overspeed. Think about performing traditional lifts at high intensity with experienced athletes and you will likely see not only an INTENT for fast movement but a resultant output with good speed, whereas eccentrically overloaded resistance training uses higher loads, and is aimed at moving as slowly as possible.
Using overspeed methods has been shown a number of times to improve speed and jumping height (2, 3) (running or jumping takeoff velocity = higher jumps), which I believe shows us the importance of letting our bodies learn how to be fast, from being fast…
Important Thoughts Going Forward
What is the best way to load eccentrically? If we need to move fast in order to increase speed than can we improve strength and speed together?
Are slow ‘supramaximal’ resistance training exercises the best for eccentric loading? Do they even produce the highest eccentric forces? What about plyometrics?
When we speak of eccentric loading, the first thought is typically on slow negatives with different barbell exercises. Do you know the extent to which we can produce eccentric peak forces in a drop jump or repeat jumps? The peak eccentric forces are 2 to 3 times that seen with a barbell, so why do we still consider this the proper way to get our body adapted to high eccentric loads? Varying our plyometric stimulus’ to expose the body to different levels of momentum heading into contraction will undoubtedly expose our system to much greater eccentric loads, while at the same time exposing athletes to high speed of movement! Should that carry over to improved performance?
I am not saying there is not a place for different loading parameters with a bar, especially where gains in strength are desired, but sometimes we need to look at what adaptations we truly seek. At FITS we use sport science to educate a lot of our decisions, so getting a good handle on the literature is an important piece of the puzzle!
1. Cook CJ, Beaven CM, and Kilduff LP. Three weeks of eccentric training combined with overspeed exercises enhances power and running speed performance gains in trained athletes. J Strength Cond Res 27: 1280-1286, 2013.
2. Ebben WP. The optimal downhill slope for acute overspeed running. Int J Sports Physiol Perform 3: 88-93, 2008.
3. Sheppard JM, Dingley AA, Janssen I, Spratford W, Chapman DW, and Newton RU. The effect of assisted jumping on vertical jump height in high-performance volleyball players. J Sci Med Sport 14: 85-89, 2011.