The Effect of Strength Training on Performance Indicators in Distance Runners
Beattie, Kris; Carson, Brian P; Lyons, Mark; Rossiter, Antonia; Kenny, Ian C; Journal of Strength and Conditioning Research. 31(1):9-23, 2017.
Last year was one of my best years of running. My training was consistent, I was happy with my races and I stayed relatively injury-free. My sleep patterns were consistent and I felt fitter and healthier in 2016 than I ever had in my previous years. That is, until September. While preparing for the cross country season, after a threshold interval workout, I noticed some tightness in my right hamstrings tendon near my knee in a group of muscles called the pes anserine. It was fairly mild to start but after each run, I noticed the stiffness increasing which then led to morning stiffness which ultimately led to me limping about 2 hours after each run. The pain was worsening. The diagnosis was a right distal and medial hamstring – a pes anserine – tendonitis. Swimming was out of the question as the kicking would aggravate it and so stationary biking it was, to try to maintain my fitness. After about 2 weeks of cross training, the tendon felt better but not 100%. After an attempt at another run, the tendon felt great during but worst about 3 hours later and the return of morning pain and stiffness. Long story short, I managed only 1 cross country race in September and the condition took about 8 weeks to recover.
An astute physiotherapist should always ask about what life was like for the runner before and during the time of injury onset. For me, I was in the midst of starting Elevation Physiotherapy, my own clinic, and my schedule was getting busier and busier. When a runner gets busy, what inevitably happens is his strength program usually falls by the wayside. This was exactly what was happening with me. I was running consistently and I was increasing my speed during my interval workouts but I had reduced my strength workouts from twice a week to about once every 2 weeks. I chose running over my strength workouts because I did not have time to do both.
This blog attempts to answer the question: What are the effects of neglecting strength training in distance runners?
This recent article by Beattie et al is eye opening.
One of the reasons why strength training is so important for distance runners is that it improves the ability of the neuromuscular system to rapidly produce force after a sustained period of high intensity exercise, like during a sprint finish. This may be a crucial differentiating factor in whether an elite athlete wins a race or comes in a close second or in improving upon one’s personal best times. It is the difference between finishing strong or fading during a race or increasing muscle strength and stiffness or sustaining a tendonitis. At a physiological level, strength training increases the stiffness between the tendon and muscles, recruits more motor units to muscles and increases their synchronization, and improves intra- and inter-muscular coordination. This translates to improved running economy and performance in runners. Think of running economy like your car’s economy. We don’t want to drive with gas guzzlers, burning fuel at a high rate and getting to empty so quickly before the next re-fueling station. An improved running economy means a runner will burn less fuel at a certain running speed over a measured distance. There are many factors that lends to improving running economy including a higher maximal oxygen uptake, improved running form, and yes, improved force production or strength.
So, this article investigated the effects of a 40 week strength training program on key performance indicators like running economy, maximal and reactive strength and the velocity achieved at maximal oxygen uptake in collegiate and national-level distance runners. He also examined body mass composition since one of the fears of most runners is that strength training leads to inevitable increases in body mass or weight gain, thus reducing running economy and efficiency.
After an 8 weeks off season, he divided runners into 2 groups: the intervention group ran and did strength training while the second control group ran only with no strength training. All the runners had no strength training experience which is a bit shocking given they were all national level runners! The intervention group did strength training 2x/week during the preseason (weeks 1-20) and once a week during the in-season “racing” season (weeks 20-40). Measurements were taken of both groups at weeks 0, 20 and 40.
Maximal Strength was assessed using the loaded squat. Reactive strength was divided into slow and fast, the latter being a plyometric-type drop jump. All physiological variables were assessed using a treadmill protocol with gas analysis using a metabolic cart.
What was the Strength program?
It was divided into 2 parts:
1. Pre-season: 2 sessions per week. Mostly maximal strength development like loaded squats with a minor element of plyometrics or reactive strength training.
2. Racing season: 1 session per week. Focus was on reactive or plyometric strength training with a minor element of maximal strength maintenance gained from the first 20 weeks.
What were the Results?
1. Maximum strength: 20-24% improvement in the strength group; control group 3%.
2. Slow reactive strength: equal improvements in both groups at 12%.
3. Fast reactive strength: 7% improvement in strength group from weeks 0-20, 15% from weeks 20-40; control group: deterioration by 2% from week 0-20, 10% from weeks 20-40.
4. Velocity at Maximal Oxygen Consumption: Strength group: increased 4%; control group no change.
5. Running Economy: 3-6% improvement in strength group; no change in the control group.
6. Body composition: No significant differences between the 2 groups.
What does this mean?
1. Strength training improves running economy in competitive distance runners, which means that they can run faster while using less fuel when training and racing.
2. Despite continued running and training in the control group, by neglecting strength training, their running economy and performance did not improve significantly.
3. Maximal strength training significantly improved maximal strength, slow and fast reactive strength during pre-season.
4. Plyometric strength training during the race season further improved their fast reactive strength by 7%.
5. When strength training is neglected and as runners continue to train and run well into the racing season, their reactive strength decreased by 9.4%. This highlights the importance of strength training to maintain a runner’s reactive strength ability and musculotendinous stiffness properties throughout the season.
6. Appropriate and specific strength training geared toward runners do not make a runner “bulk up” to the point of reducing his running economy and performance.
This to me is the mind blowing findings of this study. When runners neglect strength training, their muscle and tendons strength and stiffness will decrease. This explains why runners tend to develop injuries: the more we run, the weaker we get relatively, because our peripheral system (ie. muscles and tendons) cannot sustain the increasing training loads.
So, in conclusion, strength training for runners is a no-brainer. We have to do it and make time for it. Otherwise, we will repeat the same mistake I made in the fall of 2016. When life gets busy, do not neglect your strength routine even if it is just once a week.
Elevation Physiotherapy is now up and running and accepting new patients. Now, it is time for me to do the same, this time, returning to a 2x/week strength program! Here’s hoping Mr. Hamstrings stays quiet!