dreamingant

I've been trying for months to pinpoint my Lactate Threshold Heart Rate (LTHR) so I can devise appropriate training zones based on my LTHR. Unfortunately, I can't rationalize the expense of a lab test. And I seem to be unsuccessful at time trial testing. In any case...

My first question is: how long should one be able to ride at, or just above, LTHR? For whatever reason, I mistakenly thought it was only for a few minutes.

Second, I'm wondering if anyone might be able to help me determine my LTHR based on the figures below.

Before I bought a trainer, I attempted doing Friel's 'LTHR 30-Min Time Trial Test' on a stationery bike. And it seems completely off. My last 20-minutes produced an average HR of only 156bpm. As I've never time trialed for real, I suspect I was not going hard enough.

Normally when I do training rides, my legs begin to burn & my breathing becomes heavy at ~172bpm, which if I understand correctly, are the physical indications/manifestations of reaching anaerobic threshold. My average HR for each of my last 3 CX races (~7-10 miles long each), however, were 187, 182 & 185. If 172 is, in fact my LTHR, than I'm racing for ~50-min. in Friel's Zone 5C (anaerobic capacity). Does this make sense?

Applying Friel's 'LTHR Chart Based on Individual Time Trials' to my race-average HR (185), my LTHR would be 176bpm (185/1.05). Obviously, a CX race is different from an ITT. I've never done an ITT however, so my CX race HR is the closest statistic I have.

I typically average between 160-170bmp during most of my training rides (15-25 miles).

One time while doing a hilly, 15-mile ride, my HR hit 221bmp, but my other highest HRs were 197bpm & 195bmp (twice) - all three were hit during CX races. Do these max HRs even matter?

Would it be safe to say that my LTHR is somewhere between 172-176bpm?

Thank, in advance, for any insight you can offer.

valygrl

I'm sure someone else can do better than this, b/c my comments are purely from my own case...

IIRC, you can maintain your LTHR for an hour. I've raced and seen an average way above LT for an hour, I bet your CX races are over LT.

Before I had mine tested (blood test), I guessed my LT based on the inflection point from perceived exertion from feeling like I was working moderate to working quite hard (RPE). I guessed it was the number at which I started to whine mentally and want to slow down. I was 2 bpm low in my guess.

I'm going to say your 172-176 guess is good enough for the purpose of working out a training program. Err on the high side.

Also, to comment on other stuff... yeah it's really hard to work hard enough on a stationary bike/trainer, so I would disregard your trainer attempt, in light of your race numbers, it looks way off. And that 221 was probably jersey flap on the descents affecting your HR reading, not a true measurement.

Carbonfiberboy 

Agree the 221 is probably jersey flap. .91 * MHR is a good starting guess for LTHR. That would make it 179, except that it's unlikely you hit MHR during a CX race, unless it was in a finishing sprint. So it's probably just a little below your CX averages. CX includes running and running LTHRs are normally above cycling LTHRs.

It is hard to produce race specific LTHR numbers on a trainer. One lacks the excitement. I scream at myself, use my imagination, try to do a 10k breakaway, a leadout, etc.

I find it much easier to test it on a long, steady climb, 20 minutes or more. If you have such a thing near you, have a go. The fastest pace that gets you to the top without blowing up is at least close. Once you have that figured, you should notice that actually you could keep it up a good bit longer if you absolutely had to. I find my LTHR bounces around quite a bit during the season, higher when I'm well rested, lower when I'm training hard. Since the training zone edges are not hard anyway, and since one person's training zone edges may not comport with those of another person, best to take it all with a grain of salt and pay attention to your energy levels and training goals.

dreamingant

thanks for feedback. but if i assume 221 was a fluke (which trust me, it's crossed my mind) and 197 is actually my Max HR and 176 is my LTHR, than i am operating at 89% of max @ LTHR & 94% of max during races. is this normal? considering i'm not really even in that great shape (i'm a slow cat 4 cx racer), these percentages seem awfully high, no?

dreamingant

if you don't mind me asking, approx. how much did the lthr blood test cost? did they also do a vo2 max? upmc sports medicine facilty has a cycling performance service - they do vo2 max, lthr, critical power, etc - and i've been hesitant to contact them, assuming the service costs too much.

dreamingant

sorry for my ignorance, but was is "jersey flap?" and how did you deduce that ".91 * MHR is a good starting guess for LTHR?"

i concur. altho mentally, my exhaustion on the trainer far exceeds that on the road e.g. what should be a normal aerobic ride on my trainer feels like a hard tempo workout mentally.

valygrl

It was $100 at Boulder Center for Sports Medicine, it's normally $150 but they gave our club a discount. It was just the blood lactate test, not V02Max, and you learn your LTHR, power at LTHR, and training zones (their zone breakout, which is pretty much Friel). I wasn't really looking for a before-and-after number, so just the LT was enough info for me, to verify my guess & set training zones. You may as well call and ask how much it costs, doesn't hurt to know, right?

By "jersey flap" I meant that sometimes an HR monitor will read abnormally high - mine usually is 221 or 225 - when you don't have a good wet contact between you and the chest strap, and you are descending (or it's windy) - your jersey or other upper body clothing flaps in the wind and creates a charge that the HR monitor mis-reads as your heart rate, but really it's just a bad reading. So, if I'm wearing a particular jacket, and I'm descending, usually near the beginning of a ride b/c I'm not sweaty yet, sometimes I might see 225 when I'm just coasting downhill, and my real HR is like 90 or something.

If you have a garmin or other downloadable HR monitor, where you can track your HR to where you are / your elevation, look for a high HR during a descent on that ride where you saw 221.

Carbonfiberboy 

Valygrl has explained about the jersey flap. Not all jerseys are the same this way, BTW. Some are worse than others. Fabric, I think. Sometimes that happens when your skin dries out, too. A little saliva usually fixes it.

The LTHR estimation is from my experience with myself and other cyclists over many years. If you're well-trained, that'll be as close as it needs to be, at least until you get it sorted on the road. I've never seen a higher percentage than .92, though some people are as low as .88, but that's usually a lack of specific training.

I understand about the trainer. I think it's because we pedal without a let up. We always get a little let up on the road. After 1.5 hrs of Z2, my legs are usually starting to hurt pretty bad, which is silly because I'll average that or higher on a long ride.

dreamingant

thanks valygrl & Carbonfiberboy!

chuckb

"I find it much easier to test it on a long, steady climb, 20 minutes or more. If you have such a thing near you, have a go. The fastest pace that gets you to the top without blowing up is at least close."

That's exactly the way to do it. I had LT test done once when Cadence Cycling offered a deal on it at the LBS. They got 158 and the way it was done (power increments a little coarse) probably underestimated the LTHR a little bit. Prior efforts on long (30 minutes or more) climbs were suggesting 160-162. If you find a long enough climb, 20 minutes or more, it is almost sure to get your LTHR to high accuracy.

sabazel

I agree, it sounds like the 172 ish area is where you should be. This is average for most people, actually, so it's a good place to hang around and see how it feels.

This is how my coach describes the AT heartrate zone. Ask yourself if you can hold it for 30 minutes. The answer should be yes, but it would be difficult. You don't want to go full gas where you think "No way, I can't hold this for more than ten," but you also don't want to say, "I could hold this all day."

Also, don't all of a sudden try to do a 30 minute AT stretch without building up to it.
It took me about 2.5 months to work up to a 2x30 AT workout, I started with 4x10 w/10 minutes between intervals twice a week, then 4x12, 5x10, 5x12, then two weeks of 6x10. One week of rest (only base pace). Then 2x20 for a week with 15 minutes of rest between, then 2x25, and then FINALLY 2x30. And even then, it was still a challenge to hold the pace for 30 mintues continuously.

Sorry if that was stuff you already knew, don't want to be a know-it-all, but it was news to me the first time I heard it!

peter584

So do you test LTHR on a regular basis. If so Does anything change?

Silvercivic27

Are you by chance using the Garmin premium heart rate strap?

hobkirk

Damn youngsters with your resilient muscles!

I'm 65, started riding in June, use a Garmin 705 w/ HRM, and I push myself quite hard (but certainly not dedicated racer hard). In 5,000 miles, the highest HR I've seen during rides is 155 (climbing). My max HR during several power intervals (3 minutes as hard as possible) was 151. My highest average HR for a ride was 141 with a 154 max (18 miles pushing hard the whole way). The 141 is 90% of my 155 max.

Does that translate into my LTHR is 141?

Carbonfiberboy 

IMO, no. Very difficult to reach MHR. Certainly 3 minutes won't do it. 10-15 minutes on a trainer, going so hard that you have a friend standing by with a phone, might do it if you were well rested and had a good feel for your individual ramp-up. So don't worry about MHR. If you want to find LTHR, find a 20 minute climb and practice going as hard as possible up it. Your best steady state HR for the last half of it will be close to your LTHR, but only if you were well rested before the test. Easier to calculate a possible MHR from a known LTHR.

Even for a talented and experienced racer, it's very difficult to average LT over an 18 mile course.

hobkirk

This might prove fruitful!

My Intervals - My 3-minute efforts were maximum efforts - ready to pass out, concentrating hard to keep going straight, etc. I could not have kept it up for another minute. I did them twice and they were painful enough I didn't repeat them, despite my intentions. They were done after plenty of warm up and 2-3 minutes of very easy pedaling in-between - my HR was around 100 at the start of each interval.

1. max heart rates of 145, 147, 149, and 151 the first time (average HR of 136, 139, 140, and 143)
2. 143, 142, 142, and 142 the second time, a week later - average HR = 134, 132, 133, 134
3. I might have been working less hard on the second time but I didn't think so until I looked at the HR info

Max Effort Hour - The 18-mile rides - I got these results twice, four months apart, on the same course, a lot of hills. I hit the LAP button every 3 miles even though it was a varied 18-mile loop - the segments varied from an average ascent of 37'/mile to 97'/mile.

1. I rode as hard as I could on the flats and descents as well as the climbs
2. In August my average and max HR were 138 & 151 - it was a group ride with much stronger riders than me - I drafted about half the course - 17.1 MPH average [I'm old and fat and a novice - don't laugh - that's fast for me!] - that was in my 11th week of cycling after 1,500 miles of riding
3. In January my avg & max HR were 142 & 149 - it was a solo ride and cold (25 F) - 16.1 MPH average - in my 32nd week of riding after 5,000 miles [I was disappointed that it wasn't faster, even w/o the drafting. Even though I've concentrated on long rides, not speed.]
4. the average HR (140-146) and max HR (148-154) for each lap varied with the savagery of the climbs in that segment
5. I was panting hard the entire ride - I don't think I could have put out more effort on any one of the 6 segments

It seems like my LTHR should be contained in this data somewhere. I can't imagine terrain where there's a steady 20-minute climb - that's five miles. I know when I do a long climb my HR will crank up to 145-154 if I'm working hard and feel like I'm ready to die, but the "average" for the final ten minutes would probably be about 146, the highest average HR of the 3-mile "laps" in the intervals above.

Does that mean my LTHR is 146?

Would a 20-minute climb be any different than the above?

Carbonfiberboy 

It takes quite a while for HR to come up. I have had my best successes at attaining MHR after a 45 minute climb at LT, followed by 10 minutes at 6-7 beats over LT, followed by a hard sprint. That will usually do it. 3 minutes - no. HR is driven by hormones. One needs to get one's blood saturated with them.

The 3 minute intervals are uninteresting as far as HR is concerned. Your HRs are about what I would expect. The intervals a week later at lower HRs probably means you weren't totally recovered from whatever. I also hate 3-4 minute intervals.

Your maximum and average HRs for the 18 mile loops are close together. I suppose that's explained by the fact that you were TTing. One of the good things to do when TTing is to not blow up, IOW not get much over LT. You must not have blown up, because you seem to have had reliable results among the 3 minute segments. Therefore, one might take it that you never exceeded LT by much. If I were just going to stick my finger on a number, I'd say 150.

It's possible that you are ventilation limited. Do you run out of air before your legs pack it in? If so, I think that will improve for you over the next couple of years if you keep at it.

Yeah, eastern Massachusetts is flat or small rollers, isn't it. Got to get out west for the hills. Try to find a 5 mile stretch of fairly flat road with no stops. Exactly 5 miles is not important. Be well rested. No riding for 2 days. Warm up for 1/2 hr. At the 20 minute mark go really hard for 1.5 minutes, then again at the 25 minute mark. Arrange to be within a few minutes of one end of your course at that point. Zero your HRM and hit your course from an almost standing start. Accelerate out of the saddle and ride the 5 miles absolutely as hard as you can and still do it. You should be breathing very hard and deep the whole way. If you start to pant, ease off a bit. Keep a high cadence, 95-100 is usually good. At about the 4.25 mile mark begin accelerating. At 4.5 miles you should be going very, very hard and panting. Hold that pace the rest of the way. As soon as you get to 5 miles, stop your HRM. Your average HR will be very close to your LTHR. You may or may not achieve MHR.

Your speed is unimportant, except for comparison if you do it again. So ride on the hoods, stay a little aero, but don't inhibit your breathing. Keep your back straight and mouth and throat wide open. It's important that your course have very little downhill, if any. I find it difficult to hold LT even on a small downhill.

dreamingant

hello again, all. so, in the time since i first posted this thread, i've been tested at the UPMC Cycling Performance Center and by a local tri coach. UPMC tested me for body fat, lactate threshold (LT) and VO2max, whereas the coach just tested me for LT.

the results were somewhat embarrassing, but more frustrating, neither got me any closer to setting up my optimal training zones (based on LTHR). the problems are that a) different people call lactate threshold different names, b) lactate threshold means different things to different people, c) different people calculate training zones different ways, and d) the step-test for LT is not necessarily considered the optimal test for determining one's maximum lactate steady state (MLSS), or upper training threshold. in other words, there is very little consistency in the world of coaching and performance testing - no one seems to agree on anything. thus, i am back to doing it on my own.

one test that multiple coaches seem to agree with for determining MLSS is the 20-minute time trial method, so i am going to attempt this again this week, using ~105%* the number i now think is my LTHR (168) as my baseline ie i'm going to attempt the test at a pace that keeps my HR @ ~175bpm for 20 minutes. if this becomes too hard, than i'll know that my LTHR is lower. if it's easy, i can try increasing my HR halfway thru and see how that pans out.

*i was told by the local coach that LTHR is typically ~95% of the HR that one can maintain for the 20-minute time trial test.

UPMC considers one's LT, the point where blood lactate rises 1mmol/L above baseline. most folks consider this the lower training threshold - NOT the threshold used to base training zones on. in my case, this turned out to occur @ ~2.6mmol/L or 157bpm HR and 200watts power and 84% of my VO2max.

my test results with my local coach were pretty damn close to that.

aside: some folks consider the point when blood lactate levels reach 4mmol/L as your LT. i reached 4mmol/L at ~174bpm. but i've read that this is not an accurate method for determining one's upper training threshold.

djnzlab1

HI,
I to an older rider, I ve noticed that most riders tend to error on the easy side of their max heart rate.
I am 60 My max heart rate is 161 or their abouts, when I ride if my heart rate is over 151 I tend to huff and puf a while.
But I doubt my Lactate is near my VMAX due to training effect. As we train we build airobic potental that tends to improve ,if we test our max by little windsprints and intervals.
When I did my first time trial it was the most exhausting ride I had ever done, I was literally exhausted, I ran a fever for 4 hours. my legs ached. I was sore for about 10 hours. I believe I may have reached my VMAX,during that 23 mile ride, I doubt i could have gone 1 MPH faster that day. We frequently under estimate or capcity to exert more energy. Some people do better trying to ride in faster groups rides. I tend to like B pace, if I try A its almost painful the whole ride. My guess that A pace is near my VMAX.
Doug