Despite what some people say, I feel that due to my flat, over-pronating feet, I need a good, stable running shoe to avoid injuries. While my running volume isn't huge at around 15-20 miles a week, all it takes is one nagging injury to throw my whole training plan out of whack.
If you don't feel like logging every run you do so that you know when you've hit 300-400 miles, you can check for signs of wear on your soles. Sit your shoe on a table and look at it from behind - if it's leaning to one side, then the sole (and probably the cushioning) is worn...and it's time for some new kicks.
Of course, if you start to develop any type of pain or discomfort in your legs (knees, feet, shins, hips), this too could indicate that it's time for some new shoes.
Sure, running shoes have progressed and are now built to last longer, but technology can only do so much. At the end of the day, it is the physical limitations of nature (i.e. hard surfaces) that require us to replace our running shoes so often. The earth is unlikely to yield to the pounding force you place on it with every step and the force of gravity isn't going to change either...so if you are running in a broken-down shoe, it will be your body that suffers. The results will not be good.
Bike (2:00 hours)
10 minute warm-up
20 minutes in zone 3 (138-142 bpm)
45 minute Spin Class with some good long hills
35 minutes in zone 3
10 minute cool-down
Avg HR = 130 bpm
Max HR = 150 bpm
Run10.16 miles in 1:23:50 (8:15 min/mile pace)
Avg HR = 157 bpm
Max HR = 172 bpm
Today is going to be the hottest day of the year so far...and it was already 84° F at 5:05am this morning (see proof to the right) as I set out on my run. I struggled to keep a good pace and my HR was higher than it should have been for the speed that I was running - no doubt a direct affect of the heat!