Friday, December 28, 2007

Zen and the Art of the Endurance Ride

Most of us remember Eddy Merckx's response when he was asked for his advice for young riders aspiring to become professionals: "Ride Lots". Though Merckx is thought by many to be the greatest rider of all time, this sort of simplistic training methodology bares little resemblance to the highly specific and periodized, science based training plans of the stars of today. And in truth, even the great Eddy had a lot more structure to his training than he let on.

The difference between "just riding" and actually training with a purpose is that when you train you must recognize that every workout has a purpose. This is easy for us to forget in the fall and winter months when many of us are coming off of less structured periods of training and beginning base training composed primarily of endurance rides. Yet many of us look forward to this time of the year as a time when we can enjoy the longer, lower intensity, more social rides without the stress of a lot of intensity training, racing and traveling. Don't be misled though; there is much more to an endurance ride than "just riding". Like any other workout, an endurance ride serves a specific purpose and if done incorrectly can at best be of little training value and at worst lead to over-reaching (and ultimately over-training), injury and burnout.

Purpose of endurance rides:

- Mechanical efficiency. Though one-legged drills, fast cadence drills, riding a fixed gear bike and rollers can all help make your pedal stroke more efficient, the simple act of pedaling thousands or even millions of pedal strokes may do the most to make your pedaling as smooth and even as possible. All of this repetition should also help you to identify any bike fit or body misalignment issues (i.e. if you need to see a doctor or a chiropractor)

- Metabolic efficiency. Lower intensity rides (zones 1-3) will help teach the body to burn fat as a primary energy source. When we do Lactate Threshold tests in our lab, we can always tell when people need to spend more time developing their aerobic base because they accumulate lactic acid even at relatively low intensities (zone 1-2). Since lactic acid is a bi product of anaerobic energy production, premature lactate accumulation is a sure sign that these riders need to develop the ability to efficiently metabolize fat for energy. Burning muscle glycogen (which is in limited supply) for energy rather than fat (which there is a large supply of even in the leanest athletes) means that you will not be able to make the key high intensity efforts when it really counts.

- Improve the body's ability to transport blood and oxygen. When we talk about "aerobic fitness" this is primarily what we are talking about. High intensity exercise can also accomplish this, but these levels cannot be sustained as long and repeated bouts of high intensity exercise every day can lead to overreaching, illness and injury. Development of aerobic fitness will mean that the body will respond better to the intensity workouts that come later on.

- Muscular strength. Though muscle mass will be generated more effectively in the gym, on the bike strength training is what will make this muscle mass more functional on the bike. In order to keep heart rate and power in zone 2 uphill, it is often necessary to pedal at very low rpms. If you are able to stay seated with good form this can be an opportunity not only to keep your heart rate and power down, but also to work on cycling-specific muscular strength.

- Fat Loss. Though you will more fat in a 1 hour ride at LT than you will on a 1 hour endurance ride, you won't be able to do 1 hour LT rides every day, whereas most experienced riders are capable of completing 4, 5, and even 6 hour endurance rides on a regular basis. A typical cyclist will burn 350-800 kCal.hour on the bike, so if you need to shed some extra pounds before spring there is no better way to do it than to add endurance volume while monitoring your Caloric intake. You will still have to consume more Calories when you increase your training volume though. Cut out desserts, junk food and alcohol and cut portion size at dinner, especially on your light days or off days. Don't starve yourself on the bike. The more you eat on your rides, the more Calories you will burn and the better you will feel. If you are losing more than 1 pound per week (a caloric deficit of 500 kCal), you are losing weight too fast and should increase energy consumption and/or reduce training volume.

So how do we accomplish all of these goals most appropriately? When I examine power files from an athlete's endurance ride, this is what I look for:

- No more than 5% of the time above zone 2 heart rate. There will be times where it is difficult if not impossible to keep your heart rate down in zone 2. A little time in zone 3 is OK, but try to avoid extended periods above the upper limit of zone 2 HR.

Two graphs of heart rate distribution by zone. The first shows 11% in zone 1 and 89% in zone 2. The second shows 25% of the time above zone 2.

- Average power in zone 2. For most riders, average power for an endurance ride will fall in the low end of zone 2. Many riders go way too hard uphill and then coast or soft-pedal downhill on their endurance rides, which is more like hill sprints than endurance. Most will see power numbers at the high end of zone 3 while riding uphill and at the low end of zone 2 while riding downhill.

- Normalized power in zone 2. Normalized power better quantifies the difficulty of a ride with non-steady state efforts. I look for normalized power to be a bit higher than average power, but still in zone 2. A good endurance ride should be a relatively steady state power output, which means that the normalized power should not be dramatically higher than average power. We often describe this as "using your power meter to flatten the ride".

- Average cadence over 85. Though there will be periods of low cadence (uphill) and periods where cadence is zero (coasting), if you are pedaling, your cadence should be be 90-100 rpm unless otherwise prescribed by your coach. Factoring in uphills and coasting should produce an overall average cadence of 85 rpm or higher.

- No more than 10% coasting. Any ride will include periods of coasting such as approaching lights and stop signs and riding down steep and windy descents and this is fine. However, it is important to try to keep pedaling whenever possible. Time spent coasting is essentially time wasted. Practice shifting regularly so that you can keep your power where it needs to be on any grade. If your significant other ever gives you grief about riding your bike too much, just think of they would say when you tell them that you spent 20% of that time coasting!

A graph of cadence distribution during one group ride shows 19% of the time coasting (0 rpm)

- Steady power output and heart rate throughout the ride without a significant fade.
If a rider's power drops dramatically towards the end of the ride, it is probably a sign that they didn't eat enough. If their heart rate rises dramatically, it is usually a sign that they didn't drink enough. Unless you are pushing way too big of a gear and tearing up your leg muscles, if you fuel and hydrate properly you should feel just as good at the end of the ride as at the beginning.

A smoothed power curve from a 3.5 hour ride shows a definite drop in power. This rider did not eat enough and his power dropped 38% in the last hour of the ride.

One of the big questions riders ask about endurance-base rides is "Can I do group rides?". Group rides can often be "hammer-fests" with periods of very high intensity (usually up hills and in sprints) even if advertised as "easy winter endurance riding". For most riders, keeping heart rate and power in zone 2 and coasting time limited is difficult if not impossible. These rides may serve a purpose, but let me be clear here, they are not endurance rides. If you want to ride with a group and still accomplish the goals of the endurance ride, my advice would be to find the rides that the local pros and elite racers do. These guys may be able to race fast, but they also know how to ride slow (and do their endurance rides the right way). If you compete 9 months of the year, you look forward to the 3 months of the year when you can ride easy. Riding with experienced athletes can also be a great opportunity to pick their brains and get valuable insight into training and racing.

On the other side of the coin, if you happen to be of the stronger riders yourself, you may find that the group rides available are simply too easy. This is where riding a fixed gear bike can be extremely valuable. The uphills will help you work on cycling specific muscular strength, the downhills will help you develop leg speed and overall the fixed gear acts as a "handicap", allowing you to get a bit more out of the ride while still being able to enjoy the social aspects. If you are riding a fixed gear when other riders are on road bikes, make sure use fairly light gearing (e.g. 39x16 or 42x17), install at least one brake, and make sure to stay out of the way of the other riders on the downhills, as you will not be able to go as fast as you would on a bike that can freewheel. If you are not confident in your handling ability on the fixed gear bike, you should probably ride towards the back of the group.

As your aerobic base starts to develop, I recommend increasing the length of your longest rides to just over the duration of your longest races or events, so if your longest race will be 4 hours, your longest rides should be 4 hours. Rides much longer that this will be of limited benefit to you unless you need to lose a great deal of weight. In the later stages of base training, start to incorporate in more hills into your rides. While you should still try to stay seated and keep your heart rate in zone 2, try to carry your momentum over the small climbs better even if it leads to a short spike in power.
A good aerobic base will help prepare you for higher intensity training and racing to come. It will allow you to respond to theses stresses better and recover faster. Many may view endurance rides as "just riding", but paying attention to the details of these rides, being disciplined and patient will lead to results. Riding how you feel and ignoring the details will lead to fitness built on a shaky foundation and it will ultimately fall over like a house of cards.

Sunday, December 16, 2007

Cadence Bike Fit and Dartfish Video Analysis

Minus a pair of Zipp 999’s one of the easiest ways to increase cycling performance can be acquired in as little as two hours. A proper bike fit is the most overlooked factor in cycling performance and one of the easiest ways to increase speed. In the wrong position, an increase in fitness will not always transfer to increased speed. Correct positioning is the result of cycling experience, previous injuries, body size, flexibility, and technique.

Cycling experience is important factor because it is important to know how long an athlete has been riding in a certain position. Due to our adaptable nature it is possible to ride a saddle two inches below optimal but you will not activate the hamstring and gluteal muscles correctly, and for sure this will limit the amount of power generated.

Previous injuries can have a huge impact on your cycling position. A broken ankle from 15 years ago can change riding symmetry and result in imbalances. Many imbalances can be corrected or reduced by shimming, tiling, offsetting, etc. An experienced fit specialist will be able to explain which option is ideal for a given circumstance.

Correct cycling position is a question of arranging three contact points between the rider and bike: 1.Where the feet clip into the pedals, 2.Where the sit bones contact the saddle, 3.Where the hands/elbows hold the handlebars. The cleats are the only contact point locked into position and changes here can influence the action of the entire leg. Seat height and fore/aft position influence the transfer of power between the legs and the pedals. Aerobar height determines comfort and aerodynamics but be careful, bars that are too low relative to seat height can decrease power production. For triathletes, these factors are especially important because they must be maintained while trying to get the athlete as low and aerodynamic as possible.
A comprehensive bike fit that includes a dynamic assessment, using tools like Dartfish video analysis software, can determine if cycling posture and pedaling mechanics need improvement. This software can reveal problems with joint motions and display pre and post positions simultaneously using an overlay function that can fade in and out between the two. This software can also determine if changes made to the bike affect technique or dynamic fit, i.e. how an increase in seat height can increase ankle plantar flexion. These changes to form are not always readily apparent visually, but by using slow motion video playback or zooming in on a joint angle it can be very discernible.

The figure above displays some of the analysis tools of Dartfish. This software can accurately determine joint angles and provides instant feedback to dial in the perfect position. This rider is too compact and low on the bike in the pre position, picture on the left. By increasing seat height, moving the saddle forward, and changing the bar position the hip and knee angles increase at the top of the pedal stroke. This change increases the mechanical advantage and the power he can generate in an aerodynamic position. These changes also brought the arm angle in tighter decreasing the tension and stress on his upper body musculature.

This video analysis tool also allows us to see changes post fit otherwise not obvious with the naked eye. An increase in seat height may cause excessive planter flexion of the foot or reaching of the toes at bottom dead center of the pedal stroke. Trying to see this with the naked eye can be difficult but slowing down captured video or viewing an overlay of pre and post positions can make this very detectable. Too much planter flexion is a sign the seat has moved to high, too soon.

With all of the time and money we invest in the sport why limit your performance with a poor cycling position. A professional fit is one of the easiest ways to maximize your abilities and conserve as much energy as possible to make your overall triathlon event as successful as possible.

Thursday, December 13, 2007

How do I know if I need a bike fit?

Here at Cadence, we never cease to be amazed at how many people out there are not fit well on their bikes. I am not just talking about small issues; I'm talking about seats 3 inches too low, stems 4 cm too long and bikes 3 sized too small. The truth is, our bodies are capable of adapting to a lot. Many people do not know they have a bad fit because they don't know what it feels like to be comfortable. Maybe they just assume that riding a bike is a painful experience because that is the way it has always been for them. So I am here to tell you that it doesn't have to be that way! A good bike fit can make you more comfortable, more powerful, more efficient and more aerodynamic as well as making the bike handle better and be safer to ride.

The first step is finding out whether you need a bike fit or not. Let me make it simple; if you haven't ever had a bike fit, you should get one. Trained cyclists with years of experience may be able to develop a hyper-sensitivity to changes to their position and end up eventually gravitate to the right position, but do you really want to sacrifice your comfort and performance for all that time? Go to someone that knows what they are doing and you won't regret it. A good bike fit can be expensive, but it is an investment. Simply put, if you aren't comfortable on the bike, you won't enjoy riding. Comfort aside, how much would you be willing to pay for 50 extra watts or 30 seconds off your time in the local time trial?

Common signs that your bike fit may be off could be: knee pain or hip pain, hot spots in your feet, numbness in your pelvic region or sore shoulders and back. If always find yourself pushing bigger gears it can be a sign that your pedaling could be very inefficient. A cyclist may pedal over 5 million revolutions per year, so even a 1 percent improvement in efficiency can pay huge dividends. If you feel stretched out if you hold firmly onto the brake levers or if your wrists feel uncomfortable when you hold firmly onto the drops; you should get a bike fit. With a good bike fit, the interface between body and bike is seamless. The bike should feel like an extension of the body rather than a vehicle you are struggling to keep control of.

Below is a description of some of Cadence's "pillars of bike fitting":

Individualization: A bike fit is unique to each individual. Even two identical twins with could have very different bike fits due to differences in flexibility, core strength, body composition, riding style, and personal preferences (such as pedals and saddle choice).

Specificity: It is important to know what the rider plans to do with the bike. A rider that wants to do road races will be fit differently than one who wants primarily to ride on bike tours or charity rides. A pursuiter is fit differently from a 40K time trialist. A sprint triathlete is fit different from an IronMan triathlete.

Fluidity: A bike fit is not static. The rider will change over time and the bike fit must change as well to accommodate these changes. Riders may gain or lose weight, core strength and flexibility. They may get injured. New riders will develop riding habits over time and old riders may change their habits. It is also important to re-examine bike fit after any component changes in the contact areas of the bike. These changes include, but are not limited to pedals, shoes, saddle, handlebars and brake/shift lever type (e.g. Shimano, Campy, SRAM). Even if your fit is good to begin with, any of these component changes can throw it off. It is also important to remember that saddles and cleats wear out, sometimes very quickly. If you do not replace them, your fit will suffer. Hyper-sensitive riders or those that have important events coming up may have to make changes incrementally to ensure that they adapt to the changes without injury.

The Cadence bike fit is a comprehensive process that usually takes 2-3 hours. Before we even look at a rider on their bike, we conduct an extensive athlete interview, athlete measurements, measurements of the current bike fit setup as well as a series of flexibility assessments. We talk to athletes about their goals, strengths, weaknesses, medical history and in particular any discomfort, inefficiency or power loss that they have experienced. All of these things can provide important clues as to what the root causes of their problems might be. Once we know what the problem is, fixing it is the easy part.

A good bike fitter should always try to treat the root cause of problems rather than merely the symptoms. Since bike and body parts alike are connected and inter-related, a problem can start out in one area, but be felt in another. Treating the symptoms without questioning the root cause is like putting a band-aid on a gunshot wound. It is also important to recognize the limitations of the bike fit. A bike fit is an optimization of the human-bike interface. If there is a problem with the bike, see a bike mechanic. If there is a problem with the rider, see a doctor.

If you are interested in finding out more about our bike fitting process or you would like to schedule a fit, please feel free to email or call us at 1-800-PRO-CADENCE. A retro bike fit costs $250 in Philadelphia and $315 in New York (there is an additional charge because New York utilizes Dartfish motion analysis software as a standard part of the bike fit). And in this holiday season, a bike fit might just be the perfect present for that special someone...

Friday, December 7, 2007

Power Demands of Cyclocross Racing: Part 3

The cyclocross season is now over for many of us. For those going to Nationals in Kansas City there is one more week before the cross bikes get hung up on the hooks for the winter (that is, unless you are planning on going to World's). Coach Mike Kuhn and I had a great time going to cross races this season in the PA Series, the MAC series and the two USGPs in Trenton. With the help of Cycle-Ops, we were able to provide 10 trainers for riders to warm up on under the shelter of our tents. We were also able to get some racers to demo some sweet PowerTap 2.4 wireless wheels in their races. We were pleased to see that the wheels look good as new even after some serious abuse and riding in extreme conditions. These riders also provided us with some valuable data about the demands of cross racing.

In the first part of this series, I listed the summary data for a number of riders riding in the same race (Spring Mountain Cross). The power files we collected showed how cyclocross is extremely non-steady state, meaning that there are huge spikes in power followed by periods of zero power (while the rider is coasting, braking or running) and low power (while the rider is soft pedaling through technical sections). I theorized that the more technically proficient riders were able to spend more time pedaling, less time coasting and braking and they applied less braking force. This meant that they did not slow down as much and in turn did not have to make as much of an effort to re-accelerate. As evidence of this, the riders that performed better typically spent less time at sub-maximal power levels (defined as power outputs greater than 5.5 watts/kg) and had more "in the tank" at the end of the race to make an attack, follow an attack or close the gap on the rider in front.

Don't make the mistake that cyclocross, or any type of bike racing for that matter, is simply a matter of numbers. Certainly, riders that are more technically proficient are able conserve better and use their power when they need it most. This hardly means that the race is a lock though. The great thing about bike racing is that given the right circumstances, any rider may have the opportunity to win. The key for each rider is to design their training and race tactics well in order to have the greatest odds of success. In doing this, the power meter can be a very useful tool.

Let me give a few case studies of riders from different backgrounds, strengths and weaknesses to illustrate how we might put together a training plan and a race strategy tailored to each individual:

Dave: 25 year old endurance mountain bike racer. Dave did a few cross races last year but this year is making cross an equal priority. Dave's bike handling skills are fantastic, though he does not have much experience riding a cross bike and doing cross-specific things such as barriers and run-ups. Dave is 5'10" and 143 lbs. His Functional Threshold Power is 290 watts, 5 second mean maximal power (MMP) is 900 watts, his 1 minute MMP is 430 watts and his 5 minute MMP is 330 watts.

Kurt: 28 year old Cat. 1 road racer. He specializes in shorter road races and criteriums. Kurt is new to cyclocross and is treating it as an afterthought to the road season with no real ambitions except to have fun and improve his technical skills. He does not have a mountain bike and has never really spent any time riding off-road. Kurt is 6'0" and 168 lbs. His Functional Threshold power is 320, his 5 sec. MMP is 1500 watts, his 1 minute MMP is 700 watts and his 5 minute MMP is 450 watts.

Bob: 40 year old recreational rider/Cat. 5 road racer. He did a few road races last year but decided to give cross a try because he likes the laid back atmosphere. Although he loves to do group rides on weekends, he feels a bit intimidated by the pack aspect of road races. Bob owns a mountain bike and rides it occasionally but has never raced it. Bob is 5'10" and 180 lbs. His Functional Threshold Power is 275, his 5 sec. MMP is 1000 watts, his 1 minute MMP is 500 watts and his 5 minute MMP is 330 watts.

Let's start with Dave. Being an endurance mountain biker, Dave surely does not need to work on his endurance, especially to prepare for a 1 hour event. Likewise, his handling skills are very good so he will probably pick up the cross specific skills very quickly. For someone like Dave, the best way to do this is to get some experience in races and to do a course-simulation workout at least once a week. As cross has grown in popularity, many areas offer cross specific workouts where you will ride a short course with a group. If you do not live in an area with one of these sessions, you can find a local park or field and set up a short cross course (1.5-2 minutes) that includes some turns, some off-camber sections and 1-2 dismounts. Complete 4-6 repetitions of 2 laps "on", 1 lap "off". It is nice to vary the course each week to include different elements that you may encounter in races, such as sand, gravel, stairs, etc. After the ride, it is useful to download your power data and record average power and lap times for each lap. As a rider gains more experience, he should be able to choose his lines better and take the technical sections faster. However, with fatigue he may not be capable of producing as much power as the workout progresses, provided the "on" laps are really all out efforts.

Dave will clearly have difficulty making the hard accelerations that occur many times in cross races. In terms of race strategy, Dave will fair much better if he can ride in the front of a group. This will allow him to choose better lines and take the technical sections at speed instead riding behind less technically proficient riders and having to slow down and then sprint out of every turn. Riders behind him will not be able to take these sections as fast and will still have to make those jumps, which will wear them down. That said, Dave needs to get in front to begin with, to do that he needs to improve his sprint. It would benefit Dave to practice some cyclocross starts. To do these, you start with one foot down and then clip in as quickly as possible, go all out for 2 minutes and then settle into a pace that is just above functional threshold power for an additional 3 minutes. Although no cross race will have 5 minute periods of sustained power, this will help Dave practice the start of the race as well as improve his upper-end aerobic capacity. With practice, he should start to see the his power for the initial 2 minutes rise considerably.

Kurt is a very different case. His numbers indicate that he should be able to start well and get up to the front of the pack quickly. However, his lack of technical skills will make it more difficult on him than many other riders and he will get worn down throughout the race because he will decellerate more, and thereby have to accelerate much harder. The most important thing for Kurt is to get used to riding off road. Buying or borrowing a mountain bike and riding the trails once or twice a week could be of great benefit to him, and it could also be a fun way to maintain his endurance. If he is unable to get a mountain bike, riding his cross bike on some mountain bike trails can be equally and often even more beneficial. Because a cross bike has no suspension, you have to pick your lines very carefully. In sections that are too technical to ride, pick up the bike and run it. If you have a choice of trails, try to find terrain with a lot of twists and turns and avoid overly rocky sections, as they are unlike anything you would encounter in a cross race. Of course, use caution when doing these rides because there is little room for error when you are riding with no suspension. For more cross specific work, Kurt should also look for a weekly group cross workout. He should spend extra time working on skills such as dismounts and remounts, off-camber cornering and riding over loose surfaces. When riding off-road, look for low power averages and non-steady state power output. As you get more comfortable, try to spend more time pedaling and less time coasting or braking, which will result in higher power averages for the same relative level of exertion.

Like Dave, Kurt will want to ride in the front of his group if possible. Since he can accelerate faster than most others, he can use this to his advantage if he is in front because everyone behind him will also have to slow down more and re-accelerate harder. Riding like this could be a death sentence to a rider like Kurt. If you are worried that this type of riding will break the rules of cycling etiquette, don't be. Remember, it's a race!

Since Bob is not an experienced racer, he will have to build more general fitness than either Dave or Kurt. Although his races will last only 30-40 minutes, it is still important for him to develop his endurance by completing at least 1 longer endurance ride (2+ hours) every week. In cross season, this is best done on a cross bike because it will help you get more comfortable on the bike. If you have access to fire roads or dirt roads, riding on this kind of terrain can be ideal. As far as cross specific fitness goes, it is very likely that Bob needs to improve his ability to make repeated sprints. An excellent workout for this is a cross version of suicide drills. Anyone who has played basketball knows what I am talking about here, but for those that weren't subjected to that torture in 5th grade gym class, suicide drills are where you run as fast as you can to the foul line, turn around, run back, then sprint to the half court line, then back, then to the far foul line then back, etc... For cross, you can do these on a soccer or football field at 30, 50, 70 and 100 yards. Sprint as hard as you can off the line and make a quick 180 at the line, trying to turn in as small of a radius as possible. Make sure that you don't get bogged down in you gear and you are sprinting all out after each line. Complete 4-8 sets of these with 5 minutes recovery in between sets. Like the basketball version, it is not unusual to feel a bit nauseous. Look at your power files afterwards to see your max and 5 second power for the sprints as well as how well you are able to maintain that power as you fatigue.

Finally, like Dave and Kurt, Bob should also try to do a weekly group cross workout to prepare for the specific demands of cross racing. The one thing that Bob needs to be a bit more careful about, however, is not overdoing it. As an older rider it will take him longer to recover from his workouts than Dave or Kurt, and I would bet that if he did a group cross workout Tuesday, endurance ride on Wednesday and cross suicide drills on Thursday, he would still be tired on Saturday when the race rolls around, meaning that he would not be performing at 100%. Remember that training is a balance of stress and recovery. Doing more training than you can recover from will only lead to fatigue, illness, injury and burnout. It can be useful to examine your Training Stress Balance, or TSB (for definition, see my blog posted on 11/2). If the race is a A or B priority, the TSB should be positive going into the weekend.

For race strategy, the most important thing for Bob is to be realistic. He should look at the riders that are placing just in front of him in early season races and try to stay with them. If Bob has no realistic chance of placing in the top 10, it won't help him to kill himself to try to get to the front of the pack at the start. His best bet is to find riders that are just a little bit better than he is, try to stay with them and hopefully beat them. As he starts to do this, his goals may become more ambitious and when he starts to consistently finish in the top 5 it is probably time to upgrade.

Good luck to all those racing at National Championships this weekend and a happy winter to everyone else! I hope you have enjoyed this series of articles and I encourage you to send me any comments or questions that you may have. Thanks for reading!