Topics: Crank lengths, Glucosamine Sulphate, Heart Rate Drift, Pedaling technique - heels in or out?
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I recently purchased a new ITT bike. I’m 193cm tall, 77kg A-grade rider and want to improve my time trial position and performance. My ITT bike is setup as aero as I can make it as I am very flexible particularly in the hamstrings. I have a track bike with 172.5mm cranks (which is few seasons old) as I believe I need to spin more on the track, although I specialise in pursuits. My road bike has 175mm cranks and my new ITT bike also has 175mm cranks. My question is, would longer cranks on my ITT or track bike improve my power and speed?
Steve Hogg says:
The only answer I can give based on the info you have given is 'possibly'. There are only individual answers to this question. The only way to find out is to perform a test (your choice as to what the test is) with your existing cranks as a baseline, then get hold of longer cranks and ride them for several weeks until you feel at home on them and then perform the same test again.
Scott Saifer adds:
Steve is right that the ultimate test has to be actually riding longer cranks to see if they do well for you. In the meantime, here's a test you can do to see if there's a good chance that they will before you put a bunch of time and money into longer cranks to test.
Testing For Crank Length (done on a stationary trainer)
Step 1. Lowest Saddle Position (LSP) for Smooth Pedaling Over the Top: Pedal with one foot while the sole of the other foot rests on the trainer for support. If you can pedal smoothly over the top of the stroke 20 cycles with no "clunk", try the other foot. If you can do it with both feet, drop the saddle 3 mm and try again. If you can't, raise the saddle 3 mm. Keep going until you've found the lowest saddle setting that lets you pedal smoothly over the top with each foot. Measure the saddle height from seat collar to saddle rails.
Step 2. Highest Saddle Position (HSP) for Smooth Pedaling Through the Bottom of Stroke. This part requires extreme sensitivity or a skilled observer. Pedal with both feet. If you are currently pedaling smoothly through the bottom of the stroke with no sense of reaching, rocking or stretching and with pressure all the way to the bottom, raise the saddle 3 mm. If you are already reaching, rocking, stretching or losing power at the bottom of the stroke, lower the saddle 3 mm. Continue until you find the highest saddle position that lets you pedal smoothly through the bottom of the pedal stroke with both legs. Measure the saddle height the same way as before.
Step 3. Making use of the measurements:
The Possibilities a) If HSP=LSP or HSP>LSP by less than 5 mm, your current cranks are okay but you cannot use longer cranks efficiently. Set the saddle height to HSP. b) If HSP<LSP, your current cranks are too long. To maximize efficiency, reduce crank length by 1/2 of (LSP-HSP) and round DOWN to the next lower size if the result is not an available size. Set saddle height to HSP with the new cranks. c) If HSP>LSP by more than 5mm, your current cranks are shorter than ideal.
Increase crank length by 1/2 of (HSP-LSP-5mm) and round DOWN to the next available size if the result is not an available size. Set saddle height to HSP with the new cranks.
Leg Length Discrepancy: If the high or low position seems to be different for one leg than the other, you may have a functional or anatomic leg length difference. Apparent leg length discrepancies are corrected by body-work and/or cleat shims. It is possible to complete the crank length test by focusing on one leg at a time even with a leg length discrepancy. If the two legs indicate different crank lengths needed, choose the shorter length.
I m experiencing a bit of knee pain issue by way of overload after a couple of 24hour solo events. I’ve heard a lot of promising things on glucosamine sulphate. Would you blindly recommend it? Is there any brand you prefer? And what are the details I have got to pay attention to?
Scott Saifer says:
The scientific research is actually favorable on this one. Glucosamine sulfate really does help people who have osteoarthritis of the knee. Osteoarthritis means that the cartilage in the knee has broken down, so that the space between the ends of the bones is smaller than normal. In the worst cases the cartilage is gone and the ends of the bones rub "bone on bone". Glucosamine is one of the molecules that goes into making cartilage so it makes sense that if could help repair or regenerate cartilage. It's not a general rule that eating molecules that have roles in particular processes helps improve those processes. Sometimes your body has so much of a particular molecule already that eating it doesn't help (most vitamins if you eat decently for instance) and sometimes the molecule is destroyed in digestion and would never reach the target site (any whole protein for instance).
Anecdotally glucosamine also helps people who have sore knees from athletic overuse and abuse, which also makes sense since sore knees can come from microcracks in the cartilage, which can be repaired naturally in the same way that cartilage in an arthritic knee would be repaired. Take the recommended dose on the product you buy. The research says it takes several months to be beneficial for arthritic knees, but anecdotal evidence form athletes suggests that it can help in a few weeks if the initial damage is minor. There's no benefit to taking more than the recommended dose.
There are many brands. Some manufacturers combine glucosamine with chondroitin. Last I checked there was no evidence for chondroitin, but it's not dangerous either. Some brands combine glucosamine with methyl sulfonylmethionine (MSM), which may be helpful. So far as I know, no one brand is better than another.
Also, be aware that if your knees are ending up sore because there is something off about your bike fit, arch support, shoe shape etc, you'll likely be gradually shredding your knees until glucosamine won't help, so get that fit checked and corrected if necessary.
Heat rate drift - Lowering rather rising heart rates in longer efforts?
I have an issue with heart rate drift though it seems to be the opposite of what I’ve understood that phenomenon to be. During a long effort (2+ hrs) my heart rate comes down substantially.
I’m 39 years old and have been racing competitively for 15 years, though more seriously over the last 10 or so. I’ve done 6 x 7+ day cycling races (TransAlp etc) as well as various "marathon" Mountain bike races (3 hrs – 12 hrs).
The best example I have is the once a year 67 kilometre mountain bike race "the test of metal" that I’ve done a number of times. The race takes me a little over 3 hours. Below is the download from one of the races that shows the decrease in heart rate. (I believe my max is in the low 180’s) The laps are distinctive points in the race for comparison year to year.
Lap Time Lap Time HR Max Avg Min Dist mph
1. 0:56:02.0 0:56:02.0 156 169 155 124 0 0.0
2. 1:16:17.7 0:20:15.7 151 154 144 127 0 0.0
3. 1:24:43.4 0:08:25.7 135 153 133 111 0 0.0
4. 1:27:30.0 0:02:46.6 142 144 142 141 0 0.0
5. 2:13:30.0 0:46:00.0 155 159 149 125 0 0.0
6. 2:38:15.0 0:24:45.0 144 158 144 137 0 0.0
7. 3:08:10.0 0:29:55.0 149 153 143 131 0 0.0
Is there any explanation for my heart rate coming down rather than going up?
Scott Saifer says:
There's no evidence of anything odd about your body here, but you have misunderstood the concept of cardiac drift. Cardiac drift refers to the rise of heart rate with the passage of time during exercise at a constant power output. You are simply starting hard and getting tired. Your heart rate is coming down, just as anyone else's would under similar circumstances.
You have given us a clue to how you could improve your performance however. In general the optimal pacing strategy for a 3-hour race will involve constant power output, which means that cardiac drift will cause a small increase in heart rate from the beginning to the end. In other words, if you start out easier, you'll be able maintain a higher average power and finish faster. You'll have to experiment to find out what the right heart rates for you might be, but as a starting point, aiming to stay about 5 beats below LT for the first hour would probably be close to ideal. That means you would not be breathing hard or feeling any burn in your legs for the first hour, and that you still wouldn't feel burn or breath too hard to chat if you increased the effort by 5 beats per minute.
Pedaling with heels in or out?
I was wondering if it were OK for a rider to pedal either duck footed or pigeon toed if that's also their natural running/walking pattern assuming that their knee tracking and all other metrics were good? Chris Horner seems to be a bit pigeon toed and I've seen some pros that are the exact opposite and they seem to do alright, so I was wondering why there is a constant fixation to be 100% straight?
Scott Saifer says:
The short answer is that if Chris Horner rides a certain way, and the most brilliant bike fitters and scientists say that one shouldn't ride that way, Chris is still right. Luckily in this case there's less conflict. The "correct" angle of rotation of the foot is the one that comes naturally when you are wearing cycling shoes and pedaling and that allows for good knee tracking and long rides without pain. If that is a bit toes in or out, that's okay. Occasionally we even see someone who rides well with one toe in and the other out.
There's a similar argument about toes-down vs. more flat footed pedaling. You can argue which is better until you are blue in the face, but since the Tour de France has been won with both styles, the argument is probably a waste of time. That's not to say that some riders don't generate more power or avoid injuries better in one position than the other, just that neither one is generally good for everyone.