Thanks very much for all your replies. I am running approx 8.15 per mile over 10-14 miles at the moment, so with max HR at 183 I'm probably running at about 80% of my anaerobic threshold.
When I increase my distances I suspect I'll bring the speed down to nearer 9 min miles and therefore a HR of nearer 130 which is 70% AT.
Great help this website, all new to me so thanks very much!
What a well organised, thoroughly enjoyable day yesterday. It was my first Perch and I really enjoyed the atmosphere and the weather was superb to boot.
The marshals were terrific and offered much needed encouragement, especially towards the end.
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jimbo71
