I've heard the best one to increase speed is to do intervals (alternating fast/slow). So the past week or so I've been experimenting with this. My "comfortable" running pace is about 3.5 MPH (about a 17 minute mile).
So far I have tired:
- Run 4 MPH for 5 minutes. Recover with a 3.0 MPH walk for 5 minutes. Repeat.
- Run 4 MPH for 10. Recover for 2 minutes, Run 4MPH for 8 minutes. Recover for 3 minutes. Run 4 MPH for 7 minutes. Recover for 3 minutes. Continue 10 minute cycle (6/4; 5/5, 6/4, etc).
- Run at 3.5 MPH for 5 minutes. Run at 4.5 MPH for 1 minute. Repeat many times.
- Start at 3.5 MPH. Add .1 MPH every minute until 4.1 MPH. Then reduce by .1 MPH every minute. Repeat.
Each option has included a variety of speeds and an assortment of distances. I'm not sure which one I like best. I guess I'll keep experimenting. I'm planning run a 10K at the end of the month. Hopefully the work will make difference.
This picture gave me a chuckle. I often hear sirens while I'm running and have to wonder if someone thought I was dying!