Do good racers ease up down hills and save for the up hill?

I think I was reading something by slipstream about its TTs and how they used watt meters in a recent race to ensure they eased up on watts on a downhill (where power loses its importance relative to aerodynamics) and save that energy for an uphill (where it's more about power and less about aerodynamics).

I've always aimed in tris to have constant output, but I think that it may be worth going a few MPH slower on a downhill to have the power to put out harder on the up. Is this how fast riders do it? I'm not talking about a downhill so steep you're spinning out a 53/11, but just a relatively decent downhill (say 33 mph).

 

What I like to do is hide on the uphill, attack over the crest when people are resting, power for 1/2 the downhill then sprint up the next hill. I'd usually do this on the last/second last hill though and I'll get a few who come with me....

TTs are different. I try to keep my heart rate constant so I ease up on the uphill a bit, power down the other side, and repeat coming back. You can keep a better rhythm on the flat if you keep your output constant. You don't want to let your HR plummet on a downhill.

 

There's an awful lot of evidence that you should do the exact opposite in hilly or very windy time trials. That is give your best efforts on the uphills or headwinds and go fast but not full out on the descents and tailwinds. Check out these papers on variable power time trial pacing:

http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=11083127&dopt=AbstractPlus
http://www.informaworld.com/smpp/content~content=a778564753~db=all~jumptype=rss
http://www.informaworld.com/smpp/content~content=a713808387~db=all
http://sportsci.org/jour/9804/dps.html

Basically you get the best bang for your buck using your power on the harder sections and less return for your investment going hard on the easier sections where everyone goes fairly fast and it takes a lot more power to go significantly faster.

-Dave

 

in a TT... it's definitely better to use a higher power going up hill than on the downhill. road race is different though you may want to attack on a downhill for strategic reasons. because of the nature of drag... basically the faster you go the more and more power is required to go yet faster and the next incremental increase will be even greater (gets exponentially greater)... the force increases the faster, the faster you go. but the force of gravity is constant. going downhill you will already be go ing much faster than the uphill meaning to go even faster requires way more energy downhill than to go proportionately faster uphill. uphill you will be going slower so the increase in drag to go incrementally faster will be less... basically it's much better to use you energy against a constant force like gravity than one that increase eponentially the faster you go...

 

Thanks! This makes sense...I read all the articles posted above. I suppose for wind if there is constant wind, it's moot, but in gusts a person would want to temporarily cut their effort a bit...?

Anyway, hills are the main concern, so based on the articles, they advise at the top of a hill continuing with a solid effort until you near terminal velocity and then easing up on the down.