Em MacIntosh
3rd Black Belt
As with anything you have to consider your personal physiology. It's a balance between microfractures that increase your bone density and joint erosion from the friction which can lead to arthritis and tendonitis and other nasty thorns. Where to find that ideal balance is different with everyone but you should consider the length of your legs and the leverage required for each step. Swimming, on the other hand, is easy on the joints but if done exclusively without proper moderation you'll lose bone density. It is essential for everyone to be able to run if they need to (and can) and it should be practiced but cautiously. There are many aspects to fitness. I'd say you'd want to up your calcium and proteine intake. I like to warm up with a light run, once I feel warmed up I sprint until I'm winded and go back to a light run to catch my breath. Once I'm exhausted is when I like to train. That works for me but may not work for another. I run every second day in order to give my bones a break to recover.