Form & Fitness Q & A
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Carrie Cheadle, MA (www.carriecheadle.com) is a Sports Psychology consultant who has dedicated her career to helping athletes of all ages and abilities perform to their potential. Carrie specialises in working with cyclists, in disciplines ranging from track racing to mountain biking. She holds a bachelors degree in Psychology from Sonoma State University as well as a masters degree in Sport Psychology from John F. Kennedy University.
Jon Heidemann (www.peaktopeaktraining.com) is a USAC Elite Certified cycling coach with a BA in Health Sciences from the University of Wyoming. The 2001 Masters National Road Champion has competed at the Elite level nationally and internationally for over 14 years. As co-owner of Peak to Peak Training Systems, Jon has helped athletes of all ages earn over 84 podium medals at National & World Championship events during the past 8 years.
Dave Palese (www.davepalese.com) is a USA Cycling licensed coach and masters' class road racer with 16 years' race experience. He coaches racers and riders of all abilities from his home in southern Maine, USA, where he lives with his wife Sheryl, daughter Molly, and two cats, Miranda and Mu-Mu.
Kelby Bethards, MD received a Bachelor of Science in Electrical Engineering from Iowa State University (1994) before obtaining an M.D. from the University of Iowa College of Medicine in 2000. Has been a racing cyclist 'on and off' for 20 years, and when time allows, he races Cat 3 and 35+. He is a team physician for two local Ft Collins, CO, teams, and currently works Family Practice in multiple settings: rural, urgent care, inpatient and the like.
Fiona Lockhart (www.trainright.com) is a USA Cycling Expert Coach, and holds certifications from USA Weightlifting (Sports Performance Coach), the National Strength and Conditioning Association (Certified Strength and Conditioning Coach), and the National Academy for Sports Nutrition (Primary Sports Nutritionist). She is the Sports Science Editor for Carmichael Training Systems, and has been working in the strength and conditioning and endurance sports fields for over 10 years; she's also a competitive mountain biker.
Eddie Monnier (www.velo-fit.com) is a USA Cycling certified Elite Coach and a Category II racer. He holds undergraduate degrees in anthropology (with departmental honors) and philosophy from Emory University and an MBA from The Wharton School of Business.
Eddie is a proponent of training with power. He coaches cyclists (track, road and mountain bike) of all abilities and with wide ranging goals (with and without power meters). He uses internet tools to coach riders from any geography.
David Fleckenstein, MPT (www.physiopt.com) is a physical therapist practicing in Boise, ID. His clients have included World and U.S. champions, Olympic athletes and numerous professional athletes. He received his B.S. in Biology/Genetics from Penn State and his Master's degree in Physical Therapy from Emory University. He specializes in manual medicine treatment and specific retraining of spine and joint stabilization musculature. He is a former Cat I road racer and Expert mountain biker.
Since 1986 Steve Hogg (www.cyclefitcentre.com) has owned and operated Pedal Pushers, a cycle shop specialising in rider positioning and custom bicycles. In that time he has positioned riders from all cycling disciplines and of all levels of ability with every concievable cycling problem. Clients range from recreational riders and riders with disabilities to World and National champions.
Current riders that Steve has positioned include Davitamon-Lotto's Nick Gates, Discovery's Hayden Roulston, National Road Series champion, Jessica Ridder and National and State Time Trial champion, Peter Milostic.
Pamela Hinton has a bachelor's degree in Molecular Biology and a doctoral degree in Nutritional Sciences, both from the University of Wisconsin-Madison. She did postdoctoral training at Cornell University and is now an assistant professor of Nutritional Sciences at the University of Missouri-Columbia where she studies the effects of iron deficiency on adaptations to endurance training and the consequences of exercise-associated changes in menstrual function on bone health.
Pam was an All-American in track while at the UW. She started cycling competitively in 2003 and is the defending Missouri State Road Champion. Pam writes a nutrition column for Giana Roberge's Team Speed Queen Newsletter.
Dario Fredrick (www.wholeathlete.com) is an exercise physiologist and head coach for Whole Athlete™. He is a former category 1 & semi-pro MTB racer. Dario holds a masters degree in exercise science and a bachelors in sport psychology.
Scott Saifer (www.wenzelcoaching.com) has a Masters Degree in exercise physiology and sports psychology and has personally coached over 300 athletes of all levels in his 10 years of coaching with Wenzel Coaching.
Kendra Wenzel (www.wenzelcoaching.com) is a head coach with Wenzel Coaching with 17 years of racing and coaching experience and is coauthor of the book Bike Racing 101.
Steve Owens (www.coloradopremiertraining.com) is a USA Cycling certified coach, exercise physiologist and owner of Colorado Premier Training. Steve has worked with both the United States Olympic Committee and Guatemalan Olympic Committee as an Exercise Physiologist. He holds a B.S. in Exercise & Sports Science and currently works with multiple national champions, professionals and World Cup level cyclists.
Through his highly customized online training format, Steve and his handpicked team of coaches at Colorado Premier Training work with cyclists and multisport athletes around the world.
Brett Aitken (www.cycle2max.com) is a Sydney Olympic gold medalist. Born in Adelaide, Australia in 1971, Brett got into cycling through the cult sport of cycle speedway before crossing over into road and track racing. Since winning Olympic gold in the Madison with Scott McGrory, Brett has been working on his coaching business and his www.cycle2max.com website.
Richard Stern (www.cyclecoach.com) is Head Coach of Richard Stern Training, a Level 3 Coach with the Association of British Cycling Coaches, a Sports Scientist, and a writer. He has been professionally coaching cyclists and triathletes since 1998 at all levels from professional to recreational. He is a leading expert in coaching with power output and all power meters. Richard has been a competitive cyclist for 20 years
Andy Bloomer (www.cyclecoach.com) is an Associate Coach and sport scientist with Richard Stern Training. He is a member of the Association of British Cycling Coaches (ABCC) and a member of the British Association of Sport and Exercise Sciences (BASES). In his role as Exercise Physiologist at Staffordshire University Sports Performance Centre, he has conducted physiological testing and offered training and coaching advice to athletes from all sports for the past 4 years. Andy has been a competitive cyclist for many years.
Michael Smartt (www.wholeathlete.com) is an Associate Coach with Whole Athlete. He holds a Masters degree in exercise physiology, is a USA Cycling Level I (Elite) Coach and is certified by the NSCA (Certified Strength and Conditioning Specialist). Michael has more than 10 years competitive experience, primarily on the road, but also in cross and mountain biking. He is currently focused on coaching road cyclists from Jr. to elite levels, but also advises triathletes and Paralympians. Michael is a strong advocate of training with power and has over 5 years experience with the use and analysis of power meters. Michael also spent the 2007 season as the Team Coach for the Value Act Capital Women's Cycling Team.
Advice presented in Cyclingnews' fitness pages is provided for educational purposes only and is not intended to be specific advice for individual athletes. If you follow the educational information found on Cyclingnews, you do so at your own risk. You should consult with your physician before beginning any exercise program.
I've had knee discomfort for 2 years first in my right now my left knee. I've had two 3-D dynamic bike fits with both showing the right hip in front or anterior to the left in the frontal plane. As expected the right knee is also held anterior or in front of the left knee. The tech's answer was:
1. Place varus wedges on cleat in right shoe.
2. No wedging in left shoe
3. Move cleat forward (foot back) on right shoe
4. Move cleat backward (foot forward) on left shoe
5. Place 2.5 mm washers between pedal spindle and crank arm bilateral to increase stance width
The first fit was in 2005 and I only had pain in right knee (lateral aspect of patella). The changes he made have finally reduced the problems with the knee so that I can ride. Now the left knee is the problem with pain along the lateral and inferior aspect of patella (same as right knee). Increasing stance width deemed necessary because of tibil varum (bowleg) bilateral. The right knee now tracks right over the right foot. The left knee however has a "varus wobble" in that the knee moves lateral to the foot at the top of the stroke with a subtle inward or medial rotation on the downstroke.
Any ideas on how I can address this issue at the hips? The tech said correcting asymmetry issues can only be made at the shoe /cleat interface i.e. moving cleat fore/aft, varus /valgus shims. How would I address this with offset seat? I've covered all bases as far as core strengthening, flexibility, etc are concerned.
Steve Hogg replies:
Your story isn't uncommon. Regarding what has been done to date.
Re 1. This is common and to be expected. My suspicion is that a largish percentage of right hip droppers start doing this at an early age to self protect their right knee from the effects of a varus forefoot. Whether the varus forefoot is pre existing or develops because of a lateral pelvic tilt I have no way of knowing. However if we become asymmetrical enough over time, then there are physical changes to pelvic mechanics that perpetuate the asymmetric way of functioning and they are hard to break out of.
Re 2. Also common and to be expected. My experience is that there are a lot of riders out there who have a significant right forefoot varus but this is absent of noticeably less on the left foot. Sometimes too, when someone functions as you do and even if they do have a left forefoot varus, it can be counter productive to wedge the left foot because the dropping and rotating forward of the right hip drags the left side towards the centre line. Sometimes, wedging a varus left foot (if you have one) can cause further problems.
Re 3 and 4. I am not a fan of this approach to functional or measurable asymmetries unless it is the least worst option amongst only bad options. What it forces you to do is use a different pattern of muscle enlistment for each leg. You're doing that already so why make it worse? .I am saying this sight unseen and your guy has seen you, so I don't want to say 100% that he is wrong but in my view the chances of this being ineffective or potentially injurious are high.
Re 5. Don't know. If it feels better stick with it. If it feels worse then remove them.
Re the wobbly left knee. The left knee moves outward on the up stroke because at the same time, you are dropping your right hip on the pedal down stroke. The left knee moves inward on the down stroke because the right side is moving back towards the centre on its up stroke.
What to do?
I disagree strongly with your tech saying "correcting asymmetry issues can only be made at the shoe /cleat interface ie moving cleat fore/aft, varus /valgus shims" Every thing you have said suggests that your issue is one of lower back and hip function. That is the start of the kinematic chain. Your feet are at the end of it. Playing with foot, cleat, pedal etc may relieve stressors (like the varus forefoot) that play a part but will make no difference to hip / lower back function. Your solution is to sit squarely on the seat.
Here is what I would do.
1. Get a long leg x ray, scan or similar to accurately determine leg length. External measurements are a guess. You need to deal in facts.
2. I am far from convinced that you have "covered all bases as far as core strengthening, flexibility, etc are concerned". If this was the case you wouldn't have the issue you have unless there was a fused or almost fused sacro iliac joint on the right side, or a partially fused S1 that was free on the left side and fused on the right side or other similar issues. If you have been doing a lot of guided stretching, it is very likely that you would become aware of issues like these if they were present. If you are left cerebella motor control dominant (left cerebellum controls right side of body) to a high degree, and this is the root cause issue (and this can be deduced from an Unterberg test) then the only tool you have to remedy that is your body. Your brain devotes space to body parts in response to the amount of stimuli it receives from them. If you need to wake up the right cerebellum / left side of body, then yoga, Pilates, Feldenkrais and similar stuff are the way to do it. We are all asymmetrical, only the degree varies. At the moment, your degree of asymmetry is causing you a problem and you need to improve to the level where it doesn't cause you a problem on bike.
Stretching and core strength training needs to be part of your daily life. Get hold of Overcome Neck and Back Pain by Kit Laughlin. Not because you have neck or back pain (though may be you do) but because that books goes heavily into asymmetries and how to work out and prioritise solutions with stretching.
Find a good structural health professional and get them to assess your pelvic mechanics. If, through this, you find any weird stuff, get back to me.
3. Move your cleats so that they are in the same relationship to foot in shoe on each side. Not the different relationship to foot in shoe that you currently have. Make sure that you have plenty of foot over the pedal as it is an aid to on seat stability. That means the centre of the first MTP needs to be in front of the pedal axle. There is plenty of stuff in the archives about that.
4. In the meantime you need a mechanical means to minimise or eliminate your right hip drop. If you hang to the right on the seat, get hold of an American Classic J post. Fit your seat to that and before locking up the single bolt tightly, lift the right hand edge of your seat as high as it will go and then tighten the bolt. This will leave you with the right hand edge of the seat tilted 5 - 7 degrees higher than the left side. This won't stop you dropping your right hip but the aim is to make the low point of the hip drop more or less level with the left hip. You may have to play around with the degree of tilt but start with the max.
Alternately, if you don't so much hang to the right but sit over to the right side of the centre line of the seat which is possible but the least likely scenario, then get back to me for an alternate solution.
5. Make sure your handlebar height and the reach to them is conservative. Forget looking low and aero for the time being. Your main concern is not to further challenge your pelvic mechanics by reaching too far down or out to the bars. Settle for a bar position that feels ridiculously easy and if necessary, modify this over time as you improve.
6. Tilting the right side of the seat up will make your right leg reach further and reduce the distance the left leg reaches. You will need to make a judgement, partly based on what you find about your leg length and partly by feel, as to whether you need to shim up the right cleat. Get back to me on that necessary.
7. Do one legged pedalling drills, BUT only with the left leg!
8. Start alternating which foot you take out of the pedals at stop signs, traffic lights and so on.
9. I assume you are right handed. If so, get out of bed 15 mins earlier each morning and develop the habit of shaving and brushing your teeth with your left hand. Hold drinking glasses in your left hand. And when you stretch, for every stretch you do, if there is a noticeably tight side, stretch the tight side, less tight side and then the tight side again and don't hold any stretch for more than 20 seconds.
10. When you hit slight rises, put some awareness into that left leg. Silently think left, left, left, left, on each left side pedal stroke. Don't do the same on the right side. During idle moments in a bunch, develop the habit of counting 50 pedal strokes on your left side.
11. Stay away from racing or tough bunch or hilly rides. When you go really hard you will automatically fall back into the asymmetrical pattern of motion that you are trying to break out of. You need to avoid that potential for the time being.
Let me know how you get on.
I've just spent 3 months in a jigsaw cast recovering from a badly fractured calcanium (heel) sustained whilst on a 3 week mountain bike holiday in Whistler, BC. I'm male, 31 years old and 59kg. I may have broken my heel throwing myself down the technical downhill trails in Whistler but I'm also a 24hr and 100km enduro mountain bike racer.
I spend a lot of training time on the road bike. I have been doing physio on my left leg for past 2 months (I could remove my cast) and my calf muscle doesn't look quite so skeletal anymore but it is substantially smaller than my right calf. My left thigh is now also smaller. I've been on my road bike on a turbo trainer for the past month to help build it up. My question is, are there any specific on bike and off bike exercises I can do solely on my left leg to even it up with the right? I don't want to start riding only to then have imbalance problems when my stronger right leg compensates too much for the weak left.
Scott Safier replies:
Answering your direct question, you can do exercises for pretty much any leg muscle one at a time easily if you have access to a decent weight room and with some effort if you don't. For instance, if you have access to a leg-press sled, you can do one legged leg press for gluts and quads, and one-legged straight leg calf-presses for calves. Most hamstring machines work equally well for one or two legs or can only do one leg.
Then of course bike-specific strength is more important than gym strength, so one-legged drills with resistance (climbing or crank up the trainer) are good.
When you do your one-legged work, remember that the real goal is being able to ride well, not just achieving balance, so rather than doing work exclusively with the left leg, work with both legs but add sets with the left leg.
Finally, a warning: for endurance riding, muscle size doesn't much matter. If you look at the guys who win, their muscles are a lot smaller than those of other guys who couldn't hope to keep up. What you should be after is balanced strength so you don't end up with compensatory injuries, rather than balanced size.
Dear Cyclingnews fitness experts,
I am a 60-year old male who had a hip replacement (BioMet metal-on-metal; the M-38A model, I think) in February of 2004 (pretty soon I will be 4 yrs post-op). I am an avid road cyclist and have logged at least 1000 miles in each of the last three years. I do mostly 15 to 30 mile rides over the rolling countryside near my town. I ride for fitness and also because I find cycling very enjoyable.
My hip feels great, my orthopaedic surgeon tells me my prosthesis looks fine in my x-rays, and he says I can ride all I want. I am actually considering the purchase of a new bicycle. The main reason is to get a bike with a triple crank to give me lower gears to make pedalling up hills easier. My current bike is a rather old model with 170 mm crank arms and only a double crank. All of the current bikes my sizes (56 cm) have slightly longer 172.5 mm crank arms. Do you think this small increase in crank arm length would have any adverse effect on my ability to pedal or the wearing on my hip joint (from the increased range of motion)? Or is the increase so small (about 1/10 of an inch) that I should not worry about it? The folks in the bicycling magazines say a longer crank arm provides more leverage so there is actually less force required to turn the pedals. I would greatly appreciate any insight or advice you could offer. Thanks very, very much.
Scott Safier replies:
I don't think you need to worry about the longer cranks changing the way your hip wears, unless your surgeon warned you to stay on short cranks. The magazines are right that the longer crank means you can apply slightly less force at the same cadence to make the same power. Some riders will find that a longer crank makes it impossible for them to pedal smoothly. You can easily test whether this will be an issue for you by simply test-riding some of the bikes you are considering buying. Any decent shop will also swap to 170 cranks for you when you buy the bike if you find that you prefer them.
Dario Fredrick replies:
Good to hear that your hip replacement has been successful to date. Your questions depend on your current range of motion. Do you have any significant limits to hip flexion particularly while pedalling? If you think about changing from 170 to 172.5 mm cranks, to maintain your current leg extension at the bottom of the pedal stroke, you will need to drop your saddle 2.5 mm. The longer crank arm also means that the top of the pedal stroke is higher relative to where you are sitting because of both the increase in crank length and slightly lower saddle position. Thus the effective change is +5 mm in pedal stroke diameter and greater hip flexion. If your hip flexion is not significantly limited on the bike and you are able to pedal your desired cadence without challenge, the longer cranks would likely be fine. Specifically regarding wear on the joint, I would ask your surgeon about the effects of repetitive hip flexion at the angle you experience in your position on the bike. Regardless of the crank length you choose, your decision to go with lower gearing for the hills sounds like a good one.
I have a question regarding Maximum Heart Rate.
I have recently purchased a polar heart rate monitor.
I have been testing my maximum heart rate over the last couple of days and am puzzled by the results. I have been using the steps in the Lance Armstrong Performance Programme.
I am 35 years old male, live in Sydney, I am 190cm tall, weigh 88 kg, am quite fit and I Ride 3-4 times a week, a combination of road and mtb single-track.
(I am riding solo in Kona 24 soon. Hope to do about 260km) Not that means anything.
During tests over the last couple of days both road riding and running, my MHR achieved is 160/min. Why? Going on traditional formula 220-age/2 = 193/min
I don't get it. Am I unfit? Are there any external factors that could influence this (dehydration?). Can I increase my MHR by training more?
I would appreciate any help on the mater
Dario Fredrick replies:
Don't worry; the number does not reflect your fitness. For trained athletes like you, maximum heart rate (HRmax) is irrelevant. It is difficult to reach, decreases with age (even if you are very fit), you would not want to train at your HRmax, and raising it does not directly raise your fitness or power. In fact, you can improve your fitness/max sustainable power even as your HRmax decreases over time.
The HRmax formulas (particularly the 220-age) have a wide error range. These formulas are very general estimations and should not replace more accurate methods of measuring training intensity, particularly for competitive athletes. Even if you could accurately and reliably measure your HRmax, Maximal Steady State (MSS = 30 min performance threshold) and training zones are not fixed percentages of HRmax. For example, you and I could have the same HRmax, but we might each time trial at very different HRs. Training zones/intensity should be based on your MSS rather than HRmax. You can use a 30 min steady-gradient climb at time trial pace as a field test to measure your MSS HR. Warm up well, avoid going out too hard and measure your average HR for the effort.
To address your other questions, dehydration can indeed affect your HR response, and you might actually see higher HRs for the same relative workload if you are not well-hydrated. Also, stimulants such as caffeine or ephedrine can raise HR for a given workload. Finally, there is no need or benefit to raising your HRmax (or MSS HR for that matter). Your training may actually decrease your HRmax, even though you are improving. What matters is raising your power at a given HR. Finally, your running HR training zones will be a bit higher than your cycling zones (you can safely add 5 bpm as an estimation) as you recruit a larger percentage of skeletal muscle running for the same relative level of intensity cycling.
Good luck at the Kona 24!
I'm a 25 year old competitive cyclist. I've done a bike setup at a sports physician, and the following problem was brought to my attention.
According to manual measurements and observations on the trainer my left leg is overextending. I was told that my left leg is 0.5cm shorter than the right (I can't say if it's the top or bottom part of the leg).To compensate for that my left cleat was moved about 3mm forward. I've done some training with this setup and I can already feel discomfort in my left knee. Should I leave this cleat position like this or change it back to my old position (was according to Steve's suggestions).
My feet have also an inwards angle. (In other words, my normal walking shoes is worn out excessively in the insides at the front foot and the rear foot). It was suggested that I use 2 LeWedges under each cleat (thick side of wedge to be inwards). Should I try to fit another 3mm spacer under the wedges of the left leg to compensate for the leg length difference?
Thank You I appreciate your help.
Steve Hogg replies:
Small leg discrepancies, like the 5mm you have been told is the difference, are notoriously hard to measure externally. The only definitive way is by long leg X ray, MRI or similar. However I accept that you are overextending on the left leg, whether because of a measurable leg length difference or an on seat pelvic asymmetry. As you have probably read on this forum, my experience is that 95% of people drop their right hip while pedalling a bike and 5% drop the left hip. For many this is inconsequential because the degree of hip drop is so small that realistically, it doesn't make much difference.
But for many, it does cause problems. Any tendency to the dropping of one hip can be exaggerated by a seat height that is even a touch too high or a reach down and out to the bars that is too great because both will tend to destabilise the rider on the seat.
Okay, that's background info. Replace your left cleat where it was. I am not a fan of differential cleat position except when presented with exceptional circumstances. Most of the time it causes problems and your experience to date would seem to confirm that. Once you have done that, drop your seat a few mm and see whether the left leg feels as strong as the right. If so, great and enjoy riding your bike.
If not, then you will need to fit a small shim under the left cleat. I would try 3mm as a starting point. If you need to use much more than that, you will need to move the cleat 1mm further back relative to foot in shoe for every 5mm of shim stack that you use. This will work to negate any extra rocking torque that placing a shim underneath the cleat may cause.
If you are unsure what shim size to use, test any particular stack by riding up a steepish hill on the seat. You will need a following rider to tell you whether you are dropping that right hip. If that is the root cause issue and it is exaggerated when climbing ( which is likely), then get back to me for a solution.
I enjoy reading your column and have learned a great deal from it. My inquiry is concerning a scar I have just below my knee. I fell while riding a few months ago and scraped up the skin below my knee. While it was healing, I kept it covered with antibiotic ointment and a bandage. Now, there is a big scar there. I've been putting Vitamin E on it 1x/day for several weeks and not really seeing any change yet. Do you know of other treatment methods and their pros and cons to reduce the appearance of scars from "road rash"?
Scott Safier replies:
I just checked my knee and my scars are fading but they are still there too. It's only been about 12 years since the crashes though, so I'm still hoping...
So far as I know, other than cosmetic surgery there is no way to get completely rid of road-rash scars.
Stretching for cyclists
Feb 06 l had a femoral osteotomy and lower limb internal rotation. I also had about 24mm of femur removed to correct a leg length discrepancy. August 07 I had the hardware removed from my femur. I have now started back training, and am now seven weeks into my adaptation stage in the weight room. In the last week I have had a slight twinge in my right knee on the outside where the ITB attaches (the same side as surgery).
Can you recommend any good stretches specific to cyclist for stretching the IT band?
If the pain gets worse or there is no improvement l will go back to my physio.
Dario Fredrick replies:
You can find a sample of the Yoga for the Cyclist Handbook here. The three yoga poses in the handbook sample specifically address the hamstrings, hip rotators and IT band. Let me know if you have any questions.
Hi Steve Hogg,
I wanted to thanks you first for helping me overcome my knee problems and move up the racing division. I am racing Cat 3 now and I am putting together a TT bike for myself and I was wondering is there any advantage to having the TT crank a bit longer than the road bike crank. My TT bike right now has a 175mm DA crank and my road bike is setup for 172.5 DA crank. I am 5'10" with normal proportions (legs are not exceptionally long and torso isn't also exceptionally long, kind of proportional). I believe my inseam is 87cms. Anyway I was wondering whether I should swap the 175mm crank out or the difference is small enough to ignore. I just don't want to wreck my knees and end up with patella tendentious again! I am not a exceptionally fast spinner, my AVG cad for my TTs is usually 85-90!
Steve Hogg replies:
Thanks for your for the thanks. Anyway, I'm happy that you got a result.
Re the crank length - with your inseam length and assuming reasonable flexibility, increasing crank length by 1.4% shouldn't make a lot of difference either way. There is always a 'but' and the 'but' is that you won't know that for sure until you test them out for a reasonable period. You are unlikely to hurt yourself by changing crank length and I know as many TT riders who use a longer crank than their usual choice as I do ones who use the same length for everything.
If in any doubt at all, stick to the length you are used to as you know there won't be a problem