I'm in a metric century next weekend on a flat course in Florida. My usual weekend rides this summer have been 40 to 60 miles, plus a 20 mile ride during the week, on rolling hills. My cycling anaerobic threshold measured 165, max hr about 185. I can pedal hard for 3+ hours, at average heart rate of about 160. During accelerations when heart rate hits 180+ I know I won't last more than a mile, or about 2 minutes. When I then sit on a wheel for 10 minutes, heart rate drops back in the 140's-150's and I'm ready to sprint up the next hill.
Strategy for metric century PR: Temp - expect 58F at start, 68F at finish. Nutrition - powerbar and water an hour before, gel 10 minutes before, carry 2 large water bottles (probably only need 1.5), second gel at 1.5 hours. Pace - this is the big question. I can TT 62 miles at 20+ mph, or sub 3 hour ride (depending on head wind). To do so I would target my heart rate in the mid-150's the first hour, low-160's the second hour, upper 160's the third hour, and all I have left the last 5 miles.
Of course it's not a TT, so I'll take whatever the peloton offers. The event is not a race, but a charity fund raiser. I expect there will be a couple of "fast" groups, followed by a trail of the full range of pace. Not knowing the crowd, how do I play it? Go out with the big dogs and hang as long as I can? If this requires my heart rate in the 160's just to hang on, should I go ahead and drop? Conventional wisdom says you can only finish with the lead pack, if you stay with them -- unlikely to find a group who were pacing themselves for the first hour and are ready to go with you to bridge up. More likely a bunch of Fred's who went out too fast and are fading in the second and third hours. Do you agree or disagree?
What's wrong with this strategy?: If the lead pack is "fast", hang as long as possible with a sub 165 average heart rate (could be 23-25mph, if I stay on someone's wheel), but drop after 20 minutes if it requires more hr.
If the lead pack is "slow" and I'm rotating through and pulling and still in my mid-150's, then organize a break to up the pace in the second hour.