Last week I wrote a blog post about core training and whether it helps with run performance enhancement. The big take away was that there is no evidence supporting a direct correlation between regular core exercise and run performance. However, doing core work stabilizes the spine and pelvis and aids in the transfer of energy from large to small body parts. When your foot strikes the ground in running, the ground reaction force shoots up your body and every joint segment of your body takes that force. For all my geeky readers, this is Newton’s 3rd Law of Motion, which states, “For every action there is an equal and opposite reaction”. With a weak core (and when muscle imbalances exist), the forces are poorly distributed (which by the way, the ground reaction force of running is 1.5-3 times body weight) and injury can ensue. When a runner needs to take time off from training due to injury, he/she misses valuable training adaptions that are “dose” dependent. The more you run, the more aerobic, physiological, and metabolic adaptions occur. Strong core = more likely to keep training = more adaptions = better performance. The equation IS NOT, strong core = better performance. It’s not that simple and neither is proper half and full marathon training which is time and dose dependent. Meaning all the appropriate doses need to take place at the right time during the training season to yield peak performance on race day and no sooner.
But I digress; If you didn’t read the entire blog post on core training last week, please do so to get the rest of the info on core training. This week I want to share what else research has supported as improving run performance, in addition to running. Plyometrics! That is right folks, dropping and jumping. In a study of talented and highly trained endurance runners, researchers assigned plyometric training prior to endurance training, twice a week consisting of countermovement jumps with arms and drop jumps at 20, 40, and 60 cm, for a six-week intervention. After the six-week experiment, the runners improved their pre-study 2.4 km time trial by 3.9% percent (Ramirez-Campillo et al., 2014). Okay, so let me break that down so it makes more sense. If someone could run 2.4 km (1.49 mi) at an 8:00 min/mi pace, his/her time for 1.49 miles could possibly improve by 28 seconds! It is important to note that explosive plyometric movements are taxing on the body and should not be done on consecutive days. In the study, the participants had 48 hours between plyometric sessions. My disclaimer here is that this type of supplementary training should also be done only in a healthy, non-injured state. If you have bum knees or an issue with your Achilles tendon, explosive movements at the foot and ankle complex is not an option for you.
So how the heck does this mechanism work anyway? Plyometrics work the stretch-shortening cycle (SSC), which is basically a stretch of a muscle followed by an immediate shortening of the same muscle. For example, in the drop jumps, you simply step off the box and as your body is descending, your muscles are lengthening (stretch) and at forefoot contact (do not land on your heals), you explosively jump vertically for maximal height. Not only does this work the important muscles of push-off for running, the plantar flexor muscles, it also uses elastic strain energy in the tendon as recoil. Interaction between the two continuous structures (muscle and tendon) influence force transmission and energy storage and return (Romanov & Fletcher, 2007). Interestingly, research has supported that 52-60% of locomotion is generated by tendons and
without elastic energy storage and return, oxygen consumption during running would be 30% higher (Magnusson et al., 2008). I don’t want to digress again, but take note, elastic strain energy is good and my yoga-loving running friends need to know that excessive yoga training can negatively affect the ability to store energy in the tendons and increase the oxygen cost of running, which in very basic terms, means it makes you a less economical runner. Oxygen consumption (use) is a measure of running economy.
For those of you that have been following the Run With Gina blog posts on Facebook or just reading on runwithgina.com, please note that in the future I will have blog posts on run training. However, my entire brand is about half and full marathon training based around injury prevention and performance enhancement through education. Without education and understanding, one cannot make good training decisions and propel forward in what they enjoy. Achieving your best as a runner isn’t about pounding the pavement for miles and miles and trying to do it faster and faster every time you hit the pavement. It is a process, that takes both patience and persistence. Your body is a temple and should be respected in that way. Be good to your body in training and it will be good to you on race day. Variety in training is good folks and so is #runwithgina, designing customized virtual training plans here, there, and everywhere!
Runner Image: Jackie Hill
Magnusson, S. P., Narici, M. V., Maganaris, C. N., & Kjaer, M. (2008). Human tendon behavior and adaptation, in vivo. Journal of Physiology, 586(1), 71-81.
Ramirez-Campillo, R., Alvarez, C., Hernandez-Olguin, C., Baez, E. B., Martinez, C.,…Izquierdo, M. (2014). Effects of plyometric training on endurance and explosive strength performance in competitive middle- and long-distance runners. The Journal of Strength and Conditioning Research, 28(1), 91-104.
Romanov, N., & Fletcher, G. (2007). Runners do not push off the ground but fall forwards via a gravitational torque. Sports Biomechanics, 6(3), 432-452.