When I’m riding, my legs (mostly quads) are my limiting factor and lactic acid buildup defeats me before I’m pushing my heart rate way up. I rarely hold higher than 170bpm on the bike for a very long time. Running, on the other hand, oxygen delivery seems to be my limiter. I regularly run with a heart rate over 170 for long stretches and my legs don’t hurt. Rather, my lungs are where I feel the hurt.
Why the difference? It’s not just a matter of HTFU, but rather what thing I’m fighting. I don’t feel like my legs are working as hard when I run and like my cardiovascular system is working really hard. On the bike, I feel like my legs are being torn apart, but my heart rate is pretty low (for me).
Am I unbalanced in some way? Should I be working to strengthen my quads in order to not have them limiting me on the bike?
Is this normal? Others have a different experience?
I’m hoping to get the professionals in on this. I have a basic understanding of how things are working physiologically, but I’d love to get experts’ input.
Thanks for the link. I hadn’t caught that article. It explains some of the issue for me.
I come from a swimming background and consider myself a stronger cyclist than runner, at least compared to triathletes. I have spent a decent amount of time with roadies, keeping up with their fast rides, but don’t think I could keep up with comparably fast runners. So, is it just a matter of cycling relying a whole lot on a few muscles and exhausting those muscles unless they’re REALLY developed?
In Dan’s article he talks about runners not being able to get their heart rates up when cycling. But did the cyclists experience muscular exhaustion (hitting lactate threshold?) when running or was it still cardiovascular?
greater O2 distribution during running from less intense muscle contractility/greater aerobic component allowing you to run at higher intensities without failure. less O2 distribution/greater anaerobic component during high intensity biking with a greater and more concentrated muscle contractility, leading to more significant lactate build-up. greater contractility leads to less blood flow, less lactate removal, less buffering capacity, etc. so your bodys response is fatigue and lower intensity, hence lower heart rate.
sorry, just rambled a bit there. i know i didnt really answer it. i’ll let the ex phys experts chime in. i’m a nutrition guy : )
Amateur here. Do you come from a running background? You’re talking about performance inhibitors in both disciplines, but how do you rank in each? Take your last triathlon (whatever distance), where did you rank relative to the crowds in the two disciplines? Did you have a stronger run split? Did you have a stronger bike split? I’m going to guess run, right? Obviously you can improve in both (unless this is really Macca posting under an alias), but which discipline is really your weakness?
My name is Chrissie Wellington, so I pretty much kicked everybody’s butts in everything.
Actually, I’m not Chrissie (and it would be scary if a woman looked like me).
In general, compared to other triathletes, my bike and run are pretty similar, with the bike maybe being slightly better. But maybe we are all just wimps on the bike. Are there any triathletes whose limiter on the run is the leg muscles and lactate? It seems like it may just be a matter of the two sports using the body differently and that unless I’m Chris Boardman my limiter on the bike will likely be my leg muscles. Am I wrong?
Oh oh can I also add that it’s unlikely to be lactic acid but lactate.
Actually it’s H+ ions if you wanna be exact. Those are just a little hard to measure so that people talk about lactate concentrations as an indirect measure.
lactic acid is building up in your legs because your cardiovascular system can’t keep up.
but it isn’t (likely) because of your lungs, but a combination of your heart, blood, mitochondria, capillarization, and things we do not even understand.
lung capacity is rarely a limiter though, even when you run =)
One thing you didn’t talk about was your cadence. If i’m pushing a big gear at under 85 rpms I’ll tend to get heavy legs and fatigued at a much lower heart rate than if my cadence is around 100.
Are there any triathletes whose limiter on the run is the leg muscles and lactate? It seems like it may just be a matter of the two sports using the body differently and that unless I’m Chris Boardman my limiter on the bike will likely be my leg muscles. Am I wrong?
Actually, I am reading your thread and thinking that I am the exact opposite. My HR will skyrocket on the bike and I can hold it high for long periods of time, but on the run it never really gets high (for me) and I cannot hold it for near as long. While I have my own theories as to why this plays out in my own case (still struggling with weight which affects me more on the run since the majority of the roads around here are flat; training background - I was a catcher in baseball and spent all of my time training for power sports and doing squats - which seemed to transfer nicely to cycling; a complete hatred for running (actually that probably shouldn’t be in pink)) I still find this interesting.
When I’m riding, my legs (mostly quads) are my limiting factor and lactic acid buildup defeats me before I’m pushing my heart rate way up. I rarely hold higher than 170bpm on the bike for a very long time. Running, on the other hand, oxygen delivery seems to be my limiter. I regularly run with a heart rate over 170 for long stretches and my legs don’t hurt. Rather, my lungs are where I feel the hurt.
Why the difference? It’s not just a matter of HTFU, but rather what thing I’m fighting. I don’t feel like my legs are working as hard when I run and like my cardiovascular system is working really hard. On the bike, I feel like my legs are being torn apart, but my heart rate is pretty low (for me).
Am I unbalanced in some way? Should I be working to strengthen my quads in order to not have them limiting me on the bike?
Is this normal? Others have a different experience?
often feel similar. but you may be riding an unnecessarily high gear. I’d suggest riding in a higher cadence. doing 90 rpm already? try 100. doing 100 already? try 120.