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Cyclingnews Fitness Q&A - September 1, 2010

By:
Cycling News
Published:
September 01, 2010, 3:14 BST,
Updated:
September 01, 2010, 6:02 BST
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Got a question for the fitness panel? Send it to fitness@cyclingnews.com. Emails may be edited for length or clarity, but we try to publish both questions and answers in their entirety.

Blood values

Hello,

I am a 28-year-old competitive cyclist. I am 170cm and weigh 65kg. I train around 13 - 15 hours a week, and make sure to include almost two high intensity training (15 - 20 minutes above 90 percent of my Vo2 max) during my week.

I turned vegan almost five months ago and I am very keen on watching my diet and taking necessary supplements (Iron & vit C, B-12, folic acid, magnesium, calcium and Vit D). I feel great and my overall performance is improving.

However, early this week I did a blood test just to monitor the impact of my vegan diet on my blood values. Below are the results compared with results of my previous test done late 2008 when I was not vegan and training around 8-10 hours a week and weighing around 70kg:

                              2010         2008

Leucocytes:       6.3               8.1
Hematies:           4.7               4.9
Hemoglobin:    14.4             14.9
Hematocrite:       43                43
Lymphocites:      42                27
MPV:                     8.3              7.3

Knowing that the day preceding my blood test I completed a very demanding ride almost three hours and 40 minutes, with around 25 minutes above 95 percent of Vo2 max, how can you explain the drop in hemoglobin but the hematocrite level remaining the same?

Do you think it is because of my vegan diet? Does it impact my performance? And what is the normal hemoglobin level for a cyclist with a similar level?

I really appreciate your feedback on this, because there are no known sports physicians in my country.

Thank you,
Khalil

Pam Hinton says:

Khalil,

Let me start by defining hematocrit and hemoglobin. Hematocrit is the proportion of your blood volume that is red blood cells, which is why the result is expressed as a percentage. Hemoglobin is an iron-containing protein in red blood cells that carries oxygen from the lungs to the rest of the body (and carbon dioxide back to the lungs).

Obviously, your training and racing are going to suffer if oxygen delivery to skeletal muscle is limited because your hematocrit or hemoglobin are too low, i.e., you have anemia.

The most common cause of anemia is iron deficiency. As you know, individuals who follow a vegetarian or vegan diet are more likely to suffer from iron deficiency than meat-eaters. The reason for this is that plant- and animal-based foods contain different forms of iron.

Animal sources of iron (i.e., especially red meat) contain heme iron, which is iron that is part of the heme protein in either hemoglobin or myoglobin. Heme iron has a much higher bioavailability than non-heme iron.

In other words, you absorb a much greater percentage of dietary heme iron. For example, a 3-ounce serving of steak contains 4mg of iron, up to 50 percent of which is absorbed in the intestine for an actual intake of 2mg of iron.

By contrast, the iron in plants is non-heme iron (i.e., the iron is not bound to the heme protein), which is poorly absorbed. For example, a one-cup serving of raw spinach contains 6mg of iron, but only 2-15 percent or 0.1-0.6mg of that is absorbed in the small intestine.

The good news for you is that, based on your blood tests, your vegan diet has not affected your iron status. The small difference in your hemoglobin result (14.4 vs. 14.9) is within the normal day-to-day variability in the measurement, which is dependent on hydration status among other things.

In addition, your values are within the expected range for a male athlete. Although you have not experienced a decline in the functional form of iron (i.e., the iron that carries oxygen in red blood cells), it is possible that you're depleting the iron you stored in you liver while you were a meat eater.

If your iron intake does meet your iron requirements, you will deplete your iron stores over time. Once this happens, then you will start to see a decrease in hematocrit and hemoglobin.

Iron stores can be measured using a blood test for ferritin (you will have to ask your physician for this test). Ferritin is an iron storage protein found in the liver and the concentration of ferritin in blood reflects your iron stores. If your ferritin is low, then I recommend that you continue taking an iron supplement.

Supplements differ in the chemical form and in the amount of elemental iron they contain. Ferrous sulfate and ferrous gluconate are the most common forms of supplemental iron because they are the most readily absorbed and cause fewer gastrointestinal symptoms (constipation, cramping).

Iron from supplements will be best absorbed if taken with citrus juice. Also, avoid taking the supplement with dairy products or tea, both of which will decrease iron absorption.

However, please note that supplemental iron is not recommended if your iron stores are normal. Unlike most other minerals, our bodies cannot get rid of excess iron. This makes the potential for iron-toxicity high, and it is possible to “overdose” on iron supplements. For this reason, don’t take more than 18mg of iron per day and have your physician monitor your ferritin levels.


Khalil then responded:

Thank you for your detailed reply, I have my ferritine level they are 144, however I do not have any baseline result to it compare to.

So with a ferritine level of 144 where do you think that places me. 1 more question how often do you advise me to take the same blood test?

Pam Hinton says:

Khalil,

Knowing your ferritin results is helpful. The ferritin cut-off for "iron depletion" is <20 nanograms per millitre, so your stores are adequate.

However, there is one caveat - high-intensity exercise performed within 48 hours of the test can increase ferritin concentrations. So, you might want to repeat the test after taking a couple of rest days. I do suggest that you repeat the tests after about 3-4 months to see if things have changed.

Good luck!

Stretching

Hi

Should I stretch prior to cycling? I recall reading somewhere that it been found to be of no benefit, there does seem to be conflicting views on this subject.

Cheers,

Dave
Westbury Wilts, England

Scott Saifer says:

Dave,

Awesome question. The answer depends on your flexibility and varies from person to person. If you can ride your bike comfortably, getting as low over the bars as you'd ever want to, maintaining smoothness and power, can keep your knees in close to the top tube while you pedal hard, can ride aerobars without losing power or ending up sore, etc, etc, etc, you don't need to stretch.

If you are in any way limited by lack of flexibility, stretching will be beneficial if you are able to eliminate the limitation.

You are right that the research generally says that stretching does not enhance bike riding ability. At the same time, most of us know someone who's knee will hurt if they don't stretch before riding, or who's back will hurt if they don't stretch before and even during a ride, so clearly some people benefit by stretching.

Shoe and anatomy

I often see the terms varus and valgus when discussing footbeds and cleat wedges. However, I don't think I understand the way in which the terms are used (this is interesting because I'm a medical student and actually do have an anatomy background).

What is the difference between forefoot varus and supination? I ask because I'm trying to understand my own anatomy with respect to pedal/cleat placement and shoe/pedal choice. In short, when I sit with my hips, knees, and ankles flexed at 90 and lower legs dangling off the table, my left foot looks significanly different than my right... I'll avoid the medical jargon, but basically the left toes point slightly out and the outside edge of my foot is significantly lower than the inside edge (which is what I would supination).

Now, I've seen in the cycling literature that this alignment is referred to as varus and that I may consider using varus wedges inside my shoes. Is the idea of a wedge to add a crutch so that the bodies mis-alignments are better supported, e.g. if the inside edge of my foot is already elevated, why should it be elevated and supported with a varus forefoot wedge? I also have a history of medial knee pain on the left, diagnosed as a symptomatic plica.

Lastly, I recently read Andy Pruitt's book Complete Medical Guide for Cyclists and was surprised to read his critique of using pedals with a great deal of play (can't remember the exact number, but I think greater than 6). He basically said that they are not good for people with particular knee injuries because they require additional stabilization (symptomatic plicae, Pes anserine bursitis, MPFL injury).

Given the forces applied to the pedal that idea seems a little strange and I was wondering if other bike fitters concurred with this idea?

Thanks,
Dan

Steve Hogg says:

Daniel,

Good questions. For ease of writing I've quoted your questions in bold and then answered them as best I can.

"What is the difference between forefoot varus and supination?"

Similar meanings. Supination occurs when there is excessive outward roll of the foot when running or walking. Re forefoot varus; As it is used within bikefitting circles, the term and position is inaccurate though the method of correction using forefoot wedges is effective in or under a cycle shoe.

True Forefoot Varus is rare and after speaking to several podiatrists with cumulative clinical experience of more than 70 years, they say that they have only seen a handful of true forefoot varus foot types.

Forefoot Varus occurs when the midtarsal joints are fixed. No rotation into pronation or supination occurs around the long axis and it is fixed in a supinatory position. Therefore the foot in a standing position or in a closed kinetic chain will pronate the rearfoot, normally to its end of joint range; that is 13 to 17 deg of heel eversion. This foot type always has an extremely low arch and the medial malleolus and medial side of the ankle complex is very prominent.

In a cycling shoe what is usually being corrected indirectly is rearfoot varus. The source of what I see as the confusion in terminology is that it is easy to create a forefoot varus in a normal foot (with a flexible midfoot) if you do not load the lateral column; i.e, 4th and 5th metatarsals and cuboids.

This loading represents the force from the ground or from applying force to a pedal and is often a corollary of rearfoot varus. The forefoot wedge, whether under cleat or inside the shoe corrects the rearfoot because the heel is not fixed to the ground. If you try correct rear foot varus by using forefoot wedges in normal walking gait when the heel is fixed on the ground, the midfoot will pronate around its long axis and damage joints by jamming them together.

This doesn't happen with varus wedges in cycle shoes or underneath a cleat as the heel is not fixed to the ground and is more or less in an open kinetic chain. However, it would be preferable when using an in shoe forefoot wedge to add a rearfoot wedge as well, especially if there is a large amount of Tibial varum.

Lastly, I'm not crazy about forefoot wedges in cycling shoes in general as they take up too much space in the toebox and can cause hot spots for some riders in endurance events. Better to wedge under the cleat or even more preferably, under the heel inside the shoe. If wedging under the heel, arch support becomes a greater necessity.

When wedging under the cleat, the whole foot is inverted including the arch. When using a heel wedge, only the heel is inverted meaning there is often a greater need for arch support than with a cleat wedge. My preference for heel wedges is because multiple cleat wedges increase the chance of the cleat moving as well as increasing the likelihood that the rider will replace the wedges in the wrong orientation when the cleats are replaced.

Heel wedges aren't a perfect solution either because if more than 3 - 5 are needed (depending on shoe size and foot shape) they can elevate the heel and make the heel fit less well in the heel cup. That means that my version of best practise can mean the maximum number of heel wedges necessary consistent with the heel cup fitting well, with any extras, if needed, under the cleat.

Where forefoot wedges are valuable is as a diagnostic tool because they are quicker to replace and a rider experimenting with wedging can put some in their jersey pocket to try different combinations during a ride. I use forefoot wedges in clients cycling shoes, but rarely.

"Now I've seen in the cycling literature that this alignment is referred to as varus and that I may consider using varus wedges inside my shoes. Is the idea of a wedge to add a crutch so that the body's misalignments are better supported, eg. if the inside edge of my foot is already elevated, why should it be elevated and supported with a varus forefoot wedge?"

The best answer I've got is that it may not... or maybe it will. A static test, as you have performed it, often has little relevance to the functional picture of what happens to the feet on a bike under load.

I use a test based on neuromuscular feedback because I find it empirically accurate in the sense that it resolves or is part of the picture of resolving issues with the feet or the fallout because of issues with the feet.

Let's assume for the sake of argument that the way that your foot hangs as you've described is what it needs to do under load. There will need to be correction. Once inside a snugly fitting cycling shoe with that shoe fixed into a pedal, your foot won't be able to assume the position you've mentioned. It will be everted relative to what you have described meaning a degree of inversion is necessary. That's when wedges come in to the picture.

What should also be part of the picture is arch support. Most cycling shoes have a woeful lack of arch support and Specialized deserve a mention for making a range of arch support insoles for their shoes.

"Given the forces applied to the pedal that idea seems a little strange and I was wondering if other bike fitters concurred with this idea?"

I don't know. I haven't canvassed opinion and I tend to take each client on their merits. This can mean that two people who display the same basic issue might require quite different solutions. Providing a solution to a problem works without causing other issues, it's valid for mine.

Broken clavicle

Hi,

I broke my clavicle at the end of June and I can't get surgery to repair it. I am riding what is left of my road bike on a trainer.

I would like to ask two questions: first one is how long should I wait till I get on a my new ride outside? The doctor says three months, but I can't wait that long.

The second is what type of weight routine can I do to increase my range of motion and increase my muscles around my collar bone?

Thanks,
Mike

Scott Saifer says:

Michael,

Many riders get back outside in less than three months after breaking a clavicle, but your doctor knows your situation far better than I do. He or she would know if there is some reason to expect slow healing, and I wouldn't, so it may be that the doctor is saying three months for a good reason.

It is also possible that the doctor is simply being conservative, giving a long estimate to be extra safe. Since the usual recovery time is more like six weeks than three months, I'd suggest a follow up visit at about six weeks so the doctor can assess the rate of healing and tell you if you are ready to go outside or if you need more time.

The doctor should also refer you to a physical therapist for the range of motion and flexibility you want when your collarbone is ready. If you are really on track to heal by three months and I tell you to make a movement now to increase range of motion when the bone is barely healed, you might end up re-breaking the weak connection the bone has just formed.

The doctor can tell you when the bone is ready for rehab, and the physical therapist knows what movements to have you do to maximize results without hurting yourself. I'm sorry not to be more positive or helpful.

More on salt loss

Hi,

After reading your Q & A on replacing salt I was compelled to shoot you a quick email, not to bash the article but rather to help inform your readers of a issue I have had had and come across very regularly in all levels of athlete - excessive salt loss has tremendous negative effect on performance and the body's simple ability to perform not only during exercise but also daily activities.

So to your Q and A...

Sodium is extracellular (not intracellular as quoted) meaning it is present in the bloodstream and not the cells. The other electrolytes potassium, magnesium and calcium are intracellular or present inside the cells.

Sodium being extracellular (in the bloodstream) has the biggest impact on how the body functions during activity.

Predominantly sodium as this is the key and most abundant mineral lost in sweat. As your sweat rate increases so too does the concentration of sodium. Magnesium, potassium calcium lost through sweat is very low in comparison to sodium loss.

Shotz Electrolyte Tablets are a excellent example of electrolyte replacement product dealing with that sodium loss in a way that is simple and soft on the gut.

Regards
Noel Tanner

Pam Hinton says:

Noel,

Thanks for your comment. As you correctly point out, because sodium is an extracellular cation (positively charaged ion), the amount of sodium lost in sweat exceeds losses of potassium, calcium, and magnesium, which are intracellular cations.

The amount of sodium lost in sweat is dependent on sweat volume and on the concentration of sodium in sweat. The sweat rate is determined by environmental conditions, such as temperature, wind speed, humidity, body size, acclimisation, and clothing/equipment. Likewise, the concentration of sodium in sweat varies with the sweat rate (increases) and acclimisation.

The inter-individual variation in both sweat rate and sodium concentration in sweat is large. Sweat rate varies from 0.5 to 2.0 litres per hour, and the sodium concentration ranges from 200-1600 mg Na per litre. Thus, athletes with high sweat rates might need to consume more sodium than the Tolerable Upper Intake Level (2300 mg Na per day) to replace the sodium lost in sweat.

Some of the sodium can be replaced by drinking a sodium-containing sports drink, most of which provide 500-700 mg Na per litre, at a rate of 1.0-1.5 liters per hour during exercise. However, athletes with high sodium losses might also benefit from consumption of salty foods as part of their post-workout diet, in conjuction with liberal fluid intake.

Winter training preparations

This may be a bit premature, as it is still early September, but I am already preparing for winter training. Last winter in Virginia was pretty miserable from January through March.

I have recently moved to the North Carolina mountains and I expect it to be worse. As such I am already thinking about my indoor winter training. The house I have moved into has a nice sized basement, with plenty of room to store all of my bikes.

My concern is with conditions that will limit my ability to train. As with most basements it has the potential to get pretty humid. There is very little ventilation with no central air and no real way to create cross ventilation. It already has a dehumidifier running full time to keep mould at bay. It is also quite dusty.

During my first attempts to sweep and clean was kicking up so much dust that I had to take breaks to get some fresh air. Obviously this wouldn't be ideal for spending hours on the rollers. What sort of things would you recommend for combating these less than ideal conditions and for setting up my winter training cave?

Reid
Boone, NC

Scott Saifer says:

Reid,

Since many people reading the forum are in Australia, where winter is just ending, it's as appropriate to talk about winter training now as ever.

I don't like to start with the depressing part, but your basement sounds like an awful place to train: humidity, dust and mould are not conducive to healthy living, and sucking in great lung-fulls of them while training has to be worse.

If you could possibly train on a porch, in a garage, in a gym... anywhere that can have a supply of fresh air, that would be better. If that is not to be, get a shop vacuum and a dust mask and remove the dust from your space. Get some product designed to kill mould and de-mould your space (check that its okay to breath in the space where you are using the stuff. Some of them are pretty toxic).

When you train, you're going to need a supply of cool, moving air since training is still air makes heat dissipation rather than oxygen delivery the limiter and keeps you from training effectively. You'll need a big fan to generate a breeze. I'd guess a basement would be cool enough for training, but if the basement is heated, you'll need a source of cool air as well.

Full Specifications

The Cyclingnews Form & Fitness panel

Scott Saifer (www.wenzelcoaching.com) is head coach, CEO of Wenzel Coaching.com and has been coaching cyclists professionally for 18 years. He combines a master's degree in Exercise Physiology with experience in 20 years of touring and racing and over 300 road, track and MTB races to deliver training plans and advice that are both rigorously scientific and compatible with the real world of bike racing.

Scott has helped clients to turn pro as well as to win medals at US Masters National and World Championship events. He has worked with hundreds of beginning riders and racers and particularly enjoys working with the special or challenging rider. Scott is co-author of Bike Racing 101 with Kendra Wenzel and his monthly column appears in ROAD Magazine.

Steve Hogg (www.cyclefitcentre.com) has owned and operated Pedal Pushers since 1986, 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.

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.

Pam 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 associate professor of Nutrition and Exercise Physiology at the University of Missouri-Columbia where she studies the effects of energy balance on bone health. She has published on the effects of cycling and multi-day stage racing on bone density and turnover.

Pam was an All-American in track while at the UW. She started cycling competitively in 2003 and is a three-time Missouri State Road Champion.

David Fleckenstein, MPT, OCS (www.physiopt.com) is a physical therapist practicing in Eagle, ID and the president of Physiotherapy, PA, an outpatient orthopedic clinic focusing in orthopedics, spine, and sportsmedicine care.

His clients have included World and US champions, Olympic athletes and numerous professional athletes. He received his Masters degree in Physical Therapy from Emory University and is currently completing his doctorate at Regis University.

He is a board certified orthopedic specialist focusing in manual medicine and specific retraining of spine and joint stabilisation musculature. He is a former Cat I road racer and Expert mountain biker.

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.

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.

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.

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