Your muscles might be strong, but what about your bones?
The integrity of your bones is crucial for general health and also athletic performance. We call this integrity bone mineral density (BMD). Areas such as your spine, hips, and lower legs undergo stress during everyday activity. If BMD is suboptimal, repeated stress can result in injury if one were to undergo a period of overload to the bone ie. falling, another accident, or excessive training.
What is plyometric training and how does it work?
Hopping, skipping, and jumping all qualify as plyometric training. The main premise is that a rapid and powerful movement such as a jump elicits forces up to 7x one’s body weight. This overload stresses the bone and causes the bone to remodel. When a bone remodels, it becomes stronger. Furthermore, the rapid contractions of your muscles during a jump pull on the bones, subjecting them to what is called tensile stress. When you can adapt to it, stress can be good.
I know what you are thinking. “I have to add MORE exercises to my routine?”
You might, but current research shows it does not take much to reap the benefits. A systematic review from Rodricks et. al covered 12 different studies on plyometric training, many of which featured programs with as little as 10 jumps per day and only a few times per week. You can certainly get more into the weeds with it, and the optimal dose is likely more potent, but getting two feet off the ground a few days per week is a great place to start.
In addition to improved BMD, plyometric training can have a positive impact on running performance. A systematic review from Campillo et. al found that a jump training program improved time trial performance and running economy. However, it must be noted that plyometrics/jumping cannot be a 1:1 replacement for heavy resistance training as other research indicates that lifting heavy loads plays a critical role in improving running economy. The plyometrics might be a way to improve the transferability of heavy lifting to running performance.
A simple progression
A plyometric program can be as simple as two-legged hopping. To start 2-4 sets of 20 jumps during a strength training session is sufficient. When you have mastered this, you can move on to the next phase. If you want to spice it up, grab a jump rope and knock out your reps. The video shows forward movement which is optional for this phase. You can hop in place.
A more propulsive action is bounding. This requires you to explode off of one leg much like you are during your running stride. 2-3 sets of 5 bounds each leg with a few minutes rest in between can be a great sport to start.
A final step in your progression can be a single-leg forward jump. Single-leg activities are the most difficult to perform but also the most relevant to running. You spend most of your running time on one leg and your plyos should reflect that specificity. 1-2 sets of 5-8 hops in succession on one leg, then switch to the other.
There are many other similar plyometric activities, but this progression is enough to get you started. Your options are endless. Have fun with it and remember that a small dose goes a long way.
Happy jumping!