Welcome back to the Research Decode. Today’s research breakdown is about different types of training, their impact on performance, and injury performance.
Effect of Three Different Muscle Action Training Protocols on Knee Strength Ratios and Performance.
This study was designed to compare three different training protocols on hamstring to quadriceps strength balance and functional performance. So why would someone want to study this and why should you care about the results? Well, imbalances between the strength of these two muscle groups often play a role in injuries. Most often, the hamstrings are too weak when compared to the quadriceps. This often results in either a knee injury or pulled hamstring.
The Study Design
Before explaining the study, there are two terms you need to know. I promise this is the only vocab I’ll ask you to learn today. These are two different muscle actions: eccentric muscle action and concentric muscle action.
Eccentric muscle action is basically the portion of an exercise where weight is being lowered. During the push-up, this is when you go from the top position and lower the body towards the ground. While squatting, eccentric muscle action is the portion of the squat where you go from standing to the bottom position.
Concentric muscle action is when the muscles contract. Using the previous examples of the push-up and squat, this occurs in the push-up when you go from the bottom position to the high plank position. In the squat, concentric muscle action happens when going from the bottom position to standing.
With that out of the way, on to the study design. The participants of the study were placed into one of four groups:
- Concentric training of the quadriceps and hamstrings
- Eccentric training of the quadriceps and hamstrings
- Concentric quadriceps training and eccentric hamstring quadriceps training
- No training
The groups each followed a six-week training program after undergoing testing for strength, function, and power. At the end of the training programs, the participants were tested again.
Results
For results, we’ll break it down by each training group.
1. Concentric training of the quadriceps and hamstrings
This group showed an increase in the rate of force development, meaning that it showed an increase in explosive muscle strength.
2. Eccentric training of the quadriceps and hamstrings
This group saw an improvement in the hamstring:quadriceps strength ratio as well as an increase in peak force and performance on jumps requiring eccentric muscle actions such as depth jumps.
3. Concentric quadriceps training and eccentric hamstring quadriceps training
No major changes in performance were seen with this group.
4. No training
As you might expect, no changes occurred in this group.
What does this all mean?
The main takeaway from this study should be to integrate eccentric muscle action to your leg training to help guard against future injuries. Weak hamstrings are a risk for hamstring strains and ACL tears. Eccentric training of the hamstrings and the quadriceps help to protect the knee.
However, this doesn’t mean you should only use eccentric training. The finding from group 1 is important, especially if you are playing sports that require explosive movements. The easiest solution is to include both eccentric and concentric muscle action into your training. Start by looking at your sport and what is required and go from there.
If you are looking to integrate this into your own training, but don’t know where to start, contact us. Working with us, we can create a plan to keep you performing at your best.
Ruas, C. V., Brown, L. E., Lima, C. D., Costa, P. B., & Pinto, R. S. Effect of three different muscle action training protocols on knee strength ratios and performance. The Journal of Strength and Conditioning Research, 32(8), 2154-2165.