zxcvzxcvzx wrote:
You can do great treadmill tempos because first the lack of wind resistance on the majority of your front surface area (that is upper body, excluding arms; your arms and legs are moving into still air, of course), while somewhat balanced by the lack of cooling air if you don't have a fan, allows you to get up to a high speed and the mentality of refusing to press the down button to slow you down can really help you push to the end of a long tempo. I've done sub 26 5M on the tmill even with 1%, but never beaten 26:40 on the road for a tempo. It forces you to go fast and you adjust and get faster. And in the summer you may have no one to train with to get you going and it is probably too hot to get any decent pace. The drawback is that you don't acclimate to the heat, which you will still probably have to contend with for at least the first month of xc.
You're getting in excellent shape for xc and shouldn't worry, but if I were you, I'd also do some of my runs outside to get acclimated better.
Interesting comment about doing tempos faster on the treadmill. After using the treadmill quite a bit I've gotten into the habit of using lap pace to go a specific speed in races and outdoor tempo runs. In the first mile of either I check my pace about 10 times, but after that it's not hard to stay at the pace I want without looking.