Thursday, July 26, 2018

Science of Strength Training for Endurance Athletes

The last year or two I've been hunting down some answers about aerobic work, capacity, it's role in recovery and a few other ideas.  In listening to the Dissect podcast, Host Mark Twight mentioned a book that led me to the work of Inigo Mujika.  While I'm waiting for Mujika's book to arrive, I did find this great presentation by Mujika at the Science Triathlon Congress.  Below the video you will find my notes.

15-18 years ago, if you had scoured the research, the overwhelming consensus was that strength training wasn't that helpful for endurance athletes.  Since then, there is lots of research to support the use of strength training.  (personal note, be careful of "best evidence" coaches have been using strength training for a long time.  even when evidence in research didn't show it worked.  Real world trumps, theory)

One study showed that in running 32% replaced some training with explosive strength training, others just 3%.  Running performance only improved int he 32% group.  Main reason was the reduction in ground contact time and reduced oxygen cost.

In a very solid study, "Short Term Plyometric in Highly Trained Middle and Long Distance Runners," plyometrics versus dynamic weight training for 8 weeks was analyzed.  Both groups showed significant improvement.  Coaches should work on periodizing both.  Key takeaway was that runners with poor running economy should focus on explosive strength training intensity.  Those that have great economy would do better with increasing volume.

For Cycling, Explosive and high resistance was key.  If done with the athletes concurrent biking, no body mass was gained.  All the KM time trials improved.  16 weeks of strength training improved their power significantly.  Since lots of biking is several hours one very impressive takeaway was that at 3 hours of steady riding tempo, a 5 min time trial was done.  Those that strength trained were able to apply much more power at the end.

Heavy weight training has been shown to improve max strength, some VO2 max measure and lower leg stiffness.  It can prevent neuromuscular fatigue.  It has been shown to decrease heart rate at the end of a 2 hour cycling task.

Mujiko is also a coach and this was his personal use of strength training.
1.  A daily core circuit ( this is something I plan on implementing)
2.  General strength off circuit training and traditional work 2x week for 8-12 weeks at 30-40%
3. Hypertrophy Strength, 2x wen for 8-12 weeks at 80%
4.  Heavy Strength, 1x for 3 weeks at 90-9%%
In addition plyometric work is done during this training.  Uses Philip Saunders Program.
He states not to be afraid of gaining weight during the hypertrophy phase as the heavy running or biking will not allow this.

Stretching studies with a met analysis of 24,000 athletes had no effect on injury prevention.  The same studies shown that proprioception helped a little, but strength training helped the most.  Most interesting, when all three were done, the results were worse then just the strength training.  This was done with triathletes.

In swimming, strength training allows the swimmer to swim the first have of a race more comfortably and have better acceleration over the 2nd half.

Some concepts on why strength training effects improvements in endurance sport.
1.  increasing the muscle size or improving neuromuscular function.  This will improve rate of force development.  Improvement in RFD, improves sprintability.
2. Increase in Type 2 muscle fibers
3.  Increase in musculotendonous stiffness.  This will improve the economy of running.

A big concept that is still controversial in my opinion is the concept of molecular interference.  He even states that this is our best practice at this point and most of this has been taken away from athletes that haven't done the concurrent training for years. 

Molecular interference means you train for an adaptation, but cancel it out with other stimulus.  Aerobic work before heavy weight training.  When there is close proximity of the two.  When you increase the intensity or the volume of the aerobic work, you will have substrate depletion and residual fatigue.  This compromises the resistance training stimulus.

The biggest problem is when you are looking for peripheral adaptation of both strength training and peripheral adaptation in endurance.  The chart shows it nicely.

One big takeaway, don't stop your training during the season, if you do, you will lose your gains.  1x a week was enough o maintain them.