Tuesday, September 24, 2024

bike sprints, trial

My first time trying sprint intervals on the bike.   I wasn't really sure what distance I should attempt for an all out sprint, so I carefully measured out a half mile and went.   It was too far, I couldn't maintain all out effort so I shortened the course to 0.3 miles, about 480m.   

I did 4 sprints all out and recorded my top speed as recorded on GPS.  Each sprint was about 40 sec.  Took ample rest between, like speed work rather than tempo.

Bike sprints - 480m (0.3 mi)

top speed: 

#1 - 29.68 mph

#2 - 29.59

#3 - 29.22

#4 - 27.05

Oddly, despite the fact I was lactic, spent, and panting after each sprint, my HR only went up to 160, probably due to the short duration, and HR peaked 30 sec after the sprint.  It was like running a hard 300m, but in some ways more effort because the resistance remains, it doesn't decrease with speed and momentum as on the track.  

It remains to be seen, but maybe this will help my sprint speed and strength more than the long climbs.

I definitely need to start wearing my helmet.  On the last one, my foot slipped off the pedal and I almost went down.  

8 comments:

  1. That’s fast. Nice job.

    ReplyDelete
  2. Seeing your pic’s standing next to your bike I often thought your footwear and pedals a risky set up. Once again get some platform pedals with studs. They work great and have great grip.

    ReplyDelete
  3. Experiencing a higher heart rate in running compared to cycling is frequently reported by people who are mainly runners. There are several proposed explanations. One is that when running (as a running expert) your muscles are well conditioned for high intensity and therefore cardiac output is the limiting factor. When cycling the limiting factor is your (slightly inferior) leg muscles as used in cycling. Running also has the intrinsic factor that you have to overcome gravity.
    More elite cyclists are able to get their HR closer to Max.

    ReplyDelete
    Replies
    1. I agree. I’ve done multiple sports at a serious level and my experience is if well conditioned for one sport that is the sport I can max out the HR. In the early 2000’s I was a very serious cyclist and tried running and couldn’t get my heart rate up with running until I got a couple weeks of training in. But even if fit for cycling I think you have to deal with more localized lactate as there are fewer muscles involved so there is more localized discomfort (quads) at a given HR. At least for normal humans. The elites I’m sure are different. A few other things from study - HR correlates to aerobic output but the correlation is different for different sports. For instance you will process just as much oxygen but at a lower HR swimming than running as the arms and legs moving give more assistance to blood flowing than legs alone - and you are horizontal. A sport where HR runs higher at the same oxygen usage is speed skating- speed skating has a gliding component where the muscles are static and not contributing to moving blood. I’m certain skate cross country skiing requires more oxygen than the hardest cycling I do but HR is not higher, it is cold and the whole body is moving helping to pump it. Consider also that the heart rate will elevate if you are over heating. Slow riding up a hill at effort will raise the HR more than the same power output going 20 MPH as the wind is cooling. HR is a very useful but imprecise metric. In cycling power output is much more valuable and directly comparable athlete to athlete, assuming accurate monitors.

      I’m pretty sure if you focused on bike sprinting your HR will rise as your power output goes up.

      Delete
    2. Yes, but I've never had HR as high for such long duration than when climbing on a bike. HR over 170 for 14 min has no parallel in my sprint interval workouts. It's really a different task and I'm beginning to question the utility and benefit of it. The thing is, the perceived effort in sprint interval training and the lactate produced seems much higher during sprint training, both on bike and running

      Delete
    3. In theory the benefit for your sport of anaerobic threshold and aerobic capacity training is improved buffering of carbonic acid which should make sprint intervals more tolerable. So sprinkling it in during season and doing more of it out of season is ok. But if you ask me what the purpose of cross training on a bike for you is, it would be to really stress the aerobic capacity component through short hard interval repeats with short recovery. The goal should not be to go as fast as possible on the bike but use the bike to really suffer so that you can tolerate running sprints better. The reason is that each sport is very specific and getting faster sprinting on the bike won’t translate to running faster. But multiple hard sprints on the bike with incomplete, active (slower riding) recovery until tongued dragged full of doubt exhaustion will develop the system wide fitness to better tolerate running sprints. I would do it 3 or so times a week for a month or two before ramping up running and drop it or reduce significantly once your track workouts pick up.

      Delete
    4. Twice a week might be enough with other cross training.

      Delete
  4. To me a successful application off off-season cross training for you would be a routine that, when you resume doing long sprints from an extended break, you can tolerate them reasonably well. Speed will only come from running but the ability to tolerate (HR recovery, general fatigue, etc) it should be modifiable with cross training.

    ReplyDelete