When getting started with a running program it’s hard on your body. Most people know this, but perhaps don’t understand why.
When you stand, 50% of your body weight is distributed on each leg.
When you stand on one leg, 100% of your body weight is on that leg.
Running is a series of hops. So if you hop onto one leg, the momentum /gravity will cause an even greater amount of weight to load onto that leg/foot.
Studies indicate that each leg must deal with up to 3-times your body weight with every running stride.
In a single 25-minute run, there’s approximate 3,700 leg impacts.
That’s a massive amount of impact force over the course of one run!
How does your body deal with running’s huge loads?
Let’s take the example of a tennis ball being dropped from the roof of a house.
When the tennis ball contacts the ground it compresses (it’s made of rubber). Then, the ball decompresses, springs back into its round shape and bounces upwards.
Now let’s turn our attention back to running.
When your foot swings forwards and contacts the ground, your body needs to absorb the force because we are not made of rubber (and hence do not bounce back up!).
The task of absorbing and controlling this force is left to your muscles, ligaments and tendons. This is called eccentric loading.
Eccentric loading (or controlling the load of your landing) means you’re using the muscles while they're being lengthened - absorbing the force in a controlled manner.
Repeated controlled force absorption causes significant muscle soreness (and can lead to common running injuries like shin splints and IT band syndrome)!
This is the reason why going for a run will cause more soreness than a bike ride if you’ve been inactive for a while. Biking does not involve controlled absorption of loads like running does.
Muscle soreness isn’t necessarily a bad thing. It means your body adapts by rebuilding and strengthening muscles fibres and connective tissues.
But you don’t want to instill too much damage, too soon.
What can you do?
Build up gradually
By building your running up gradually, you’ll give your body more time to adapt to the immense loads you’re putting on it.
It’s also worth mentioning that your cardiovascular fitness (your ability to deliver oxygen) will improve faster than your connective tissues.
Even if you feel like you can run longer than your workout prescribes, resist that temptation.
Your connective tissues need time to catch up to your fast-adapting cardiovascular system!
Mix in Lower Load Activities
You may want to sprinkle in exercises that do not contain the eccentric demands that running does.
Especially when you’re just getting started.
Examples would be:
- walking uphill
- pushing an exercise sled
Strength training is essential for running.
Simple exercises performed 2-3 times per week will provide a huge return on your investment.
Not only will strength training make your muscles and tissues more resilient, but it will also help improve your running efficiency (i.e. make running easier!).
Running puts large forces on your muscles and connective tissues.
Progress gradually and mix in activities like biking or walking uphill.
A slow progression will minimize soreness and the likelihood of injury….and perhaps most importantly, make starting a running program more enjoyable!
How to Prepare Your Body to Start a Running Program
When Should I Repeat a Week of None to Run?