Hill running is extremely popular in the running world. Coaches swear by them because they assert they are great for enhancing energy systems, economy, and strength in their athletes. As we’ve investigated recently, running uphill certainly carries its share of pros and cons, however they find their way into many coaches’ programming. Ask most coaches about whether they include repetitions on the downhill, and they will balk at the concept and mark it as “injurious” or “senseless.” It is my contention, however, that the downhill repetition can and should be as much of an ingredient in the athletes’ program as running uphill.
For those who’ve spent time in the performance enhancement world, you’ve undoubtetly heard of using slight downhill grades for “overspeed” sprinting. It is presumed beneficial because you are able to introduce a velocity to the nervous system greater than it has previously seen, which is then supposed to force the nervous system to function at higher levels and produce greater speeds. Some studies report as great as 10% faster time trials over 35 meters.
There is a fair amount of support for downhill sprinting, but what about for running?
In my studying of the subject, I’ve run across some pretty interesting case studies of downhill running. Seb Coe was said to have run his famous 800m repeat sessions under 1:50 on downhill slopes. Wake Forest’s cross country team used “the Wake Forest Drill” that included running continuously up and down a 800m hill at varying intensities. Adams State’s legendary program has used “Adams State Miles” that are both up and down hill to prepare for their seasons. Funny thing about physics, what goes up must come down at some point, so it’s obvious that the specificity of such repeats can help facilitate powerful performances.
There is also some great theroretical application to downhill running that I’ve found that show alterations in muscle structure. In two separate trials, Butterfield and colleagues and Lynn et alia demonstrated that rats exposed to bouts of downhill running adapted by adding significantly more sarcomeres in series (~12%).
What’s it matter?
To understand why, we must first understand a bit of muscle physiology. Essentially, a sarcomere is the contractile unit of muscle made up of the myofibril from one Z disc to the next. When a muscle contracts, sarcomeres shorten to create changes in tissue lengths and to create movement.
Now, if you add some sarcomeres into series, and have 112 sarcomeres where only 100 were previously, each sarcomere has to shorten significantly less to produce the same change in position. This is big for two reasons:
1. It protects your body from traumatic eccentric forces associated with downhill running and the subsequent sorness involved. For the road runner, this is extremely beneficial, and those who’ve had to walk up a flight of stairs backwards the days following a marathon can certainly attest to how much pain eccentric contractions can cause.
2. It is possible that it can make you faster as each sarcomere has to shorten less to achieve the same length. In Lynn, Talbot, and Morgan’s words, “Increased shortening velocity after training that involved lengthening contractions is compatible with an increased number of sarcomeres,” but it is important to note that, “many other factors may be involved.”
Much like uphill running, this method carries it’s fair share of drawbacks. Running downhill creates longer strides and flight times, which can be difficult to manage if an athlete is not gradually introduced to the stress. Soreness is common, and some injuries can be aggrivated by excessive downhill running.
Is it a pancea? No. Is it worth considering adding to a program? Absolutely.