Posts Tagged as "Bike Fit"

Choosing the Correct Bike

Now days you have countless choices of frames, wheels, handle bars, saddles, pedals, helmets, nutritional products and even clothing. In fact there are so many mass-produced choices that it’s just plain confusing at the best of times.

Having had a sneak preview of some of the 2011 bike ranges from the recent Eurobike show, I can’t help but wonder how many products are actually made in a factory both owned and based in the same country, let alone the same town, as the actual brand.

It’s common knowledge that a number of large brand companies have a large portion of their range made in the Far East. I think that the Chinese and Taiwanese factory owners must be laughing all the way to the bank. Good on them.

As a triathlete, however, it can be tough to decide on equipment amid the myriad of options. Bike frames and complete bikes are the hardest to choose.

Many athletes ponder questions like: which is the most aerodynamic, which is more comfortable, and, my personal favourite, which is the lightest? The truth is who cares what the answers to those questions are.

What you should be asking yourself is: does this frame/bike suit my ability; is it the right geometry for my body type and size, and, the most important one of all, does it fit into my budget?

Too many of us are caught up in the if-they-have-it-I have-to-have-it-hype.

Everyone, unfortunately, chooses a frame or bike based on what others are riding. No sooner have they bought it and the problems start.

The question most athletes are not asked when choosing a bike is: what is your injury history? This may seem a little weird but it has a significant bearing on both the style and the geometry of the bike that you may need.

Let’s take a road bike for example. You would think that the geometry on a 58cm-frame for one manufacturer would be the same as for the same size frame from all the other manufactures. Not so!

Frames can have as much as a 17mm difference in the head-tube length, which is the section on the frame between the handle bars and the top of the fork.

Let’s say you have lower back or neck discomfort. That 17mm could be the difference between you putting in a strong ride at your next race or having a shocker.

In the same instance,if you do have an old neck injury why choose a time-trial-style frame that is very low at the front thus placing even more strain on the neck than what it’s already going through?

My advice to you is simple. Ask your coach for help.

And if your coach says it is not their area of expertise, appreciate the honesty because it means that your coach is looking after your interests, rather than his back pocket.

In that case, I advise you to find a dealer that has been trained by Dr Andy Pruitt in bike fitting. What this man does not know about bike fitting is not worth knowing. Put it this way, if Fabian Cancellara trusts him shouldn’t you?

“Thanks Jono”

Jono Rumbelo, Certified ironguides Method Coach – South Africa

 

Ironman 2010 Pro-Bike Slo-Mo

If you ever wanted to see exactly how the pros set their bikes up this is the video to do that. Perfect

Bike Fit vs. Your Bike Technique

After doing some research on bike fit and technique I realized that this article from http://triathlete-europe.competitor.com is simply as good as it gets.

A lot has been made about bike fitting in recent years. But while qualified fitters can undoubtedly have a massive impact on your speed and comfort, they do not always offer an absolute solution. Sometimes there are slight alterations that you can make in your own technique that can have a huge impact on the way you perform on the bike.

By Jason Goldberg
Something has been lost in the recent bike-fitting craze. We’ve forgotten that it’s not just about the bike. The typical fitting is all about setting up the bike to support an assumed position of the rider. The goal is a setup that creates an optimal blend of comfort, power and efficiency, but to actually get this result, a fitter must devote just as much attention to the rider’s position, which cannot be taken as a given. Unfortunately, few fitters know much about rider positioning.

Worse, many triathletes don’t even bother to seek out qualified fitters to work on their positioning. On many triathlon forums, people post side-view photos of their positions and ask board members to critique them. The problem here is twofold. One issue is that air hits you from the front as you cut a hole through it, not from the side. The second issue is that most of the people replying with positioning advice have never been in a wind tunnel nor are experienced fitters. In other words, they don’t know what they’re talking about. Let’s look at what wind tunnel testing and real-world experience at the elite level tell us about proper positioning.

There are three major forces that will hold you back when riding your bike on a flat to rolling course: mechanical resistance, rolling resistance and wind resistance. Mechanical resistance is the least important. It is generated by the gears of your bike, which are fairly efficient, especially on a race-tuned bike, and in the bearings, which are also quite efficient. Rolling resistance is a little more complicated, as it varies by tire construction, inflation pressure and surface smoothness.

Both mechanical and rolling resistance increase in a linear manner, but wind resistance is different because, assuming that there is no change in your body riding position, it increases at the square of the increases in speed. The drag on a cyclist traveling at 20 mph is four times as great as the drag at 10 mph. Thus, the faster you go, the more power is required to overcome wind resistance. In any given riding position, you need about 33 percent more power to go 10 percent faster. The good news is that you can reduce wind resistance at any given speed by manipulating your position. The key is to cut down the frontal area of your position, forming your body into a more streamlined shape on your bike. Watch the Tour de France and you can tell which teams and athletes take this streamlined position seriously and which do not. The same goes for the front of most professional non-drafting triathlon fields.

A rule of thumb developed by Steve Hed, of Hed Cycling Products in Shoreview, Minn., is that you can save three seconds over 40 kilometers for every 10 grams of drag dropped. There are 454 grams in a pound; therefore, dropping a pound of drag can save you roughly 2.5 minutes over 40 kilometers and more than 11 minutes over an Ironman bike course.

Reducing Drag
The most effective positioning change you can make to reduce drag is to lower your head as much as you can toward your hands. This change alone has been shown reduce drag by more than 200 grams in the wind tunnel. Taller athletes typically cannot get their head as close to their hands as shorter athletes because of the length of their upper arms. They can overcome this disadvantage to some degree by angling their forearms upward. When this is done properly, you can actually hear the wind resistance decrease.

The next biggest time savings comes from repositioning your shoulders. The objective here is to narrow your shoulders by rolling them inward. To do this, get into your riding position indoors and look directly into a mirror. See if there is a way to “shrug” your shoulders to make yourself narrower. Modifying your elbow and hand position might make it easier.

The more your shoulders roll in the narrower your shoulders will get and the faster you will be. This can save you another 100 to 200 grams of drag. Again, angling your aerobars slightly upward might enable you to narrow your shoulders more comfortably. Moving your elbows closer together may also help. We use giant calipers that we call “manipers” to measure shoulder width and ensure that as the elbows come closer together, the shoulders follow. Eventually, you will get to a point where your shoulders are unaffected by further reductions in the distance between your elbows, and that’s the point where you’ll want to stop.

Aero Positioning
There is no apparent effect of aerobar shape and aerodynamics. S-bends offer the most powerful position but are not necessarily the most comfortable. Finding a balance between power and comfort is important. While pulling up on the bar (which is a real power position), the more rotated your wrist becomes, the more leverage you can generate. The more angle there is in a single bend, the less power you will have pulling up.

The variety of hand positions that are possible with S-bends makes it easier to find a position that optimizes power and comfort. The key to proper S-bend positioning is to make sure that your ring finger is lined up with your elbow. This will prevent the wrist and forearm discomfort often seen with ill-fitted S-bend aerobars. Also, avoid angling your aerobars downward. This not only increases your frontal area, it also raises your effective bar height, causing you to ride “taller” and further increasing your frontal area.

Many triathletes assume that the surest way to increase the aerodynamics of the riding position is to drop your bars and lower your torso, but this is not always the case. A better indicator of aerodynamic positioning, from a side view, is how low the head is. A greater sternum angle may actually facilitate a lower head position because the rider is not forced to keep his or her head back to see forward.

Using a goniometer, we measure an athlete’s sternum angle rather than hip angle. It is certain that if your sternum angle goes below five degrees, you will be slower than if it were at five to 15 degrees. We actually raise some riders because their net drag is unaffected by going a little higher, as the steeper their torso angle is, the more they can lower their heads.

This is not to suggest that your back position is not important to aerodynamics. However, what matters is not how low it is but how you hold it. You want to strive for a slight curve in your mid-spine, almost like a hump. This will help integrate your aero helmet into your streamlined position. Specifically, it will help smooth airflow over your aero helmet, integrating your aero tuck into a neat little package and lowering your drag numbers another 50 to 100 grams.

There is a principle in aerodynamics that states that air likes to flow over curved surfaces as opposed to flat ones. Consider the toroidal bulges of aero wheels versus flat sidewall wheels. If you have a naturally flat back, work on curving your back into a hump, and if you have a humpback, rejoice, because it will help you ride faster.

It is important to note that the best time triallers and triathletes in the world all work very hard to make the unnatural natural. Almost everyone who attempts to modify his or her position according the guidelines I’ve just given you comes back to me after the first few rides complaining about feeling uncomfortable.

Be patient, as it takes time to first get into the right position and then learn to pedal, steer, corner, drink and feed in it. When it does become tolerable and eventually comfortable (and it always does), your persistence will be rewarded with significantly faster bike-splits.

Trigger Point Bike Fit

1. Soleus
*Maximum elasticity (massage) allows the soleus muscle to expand to its fullest capacity in order to transfer power from the quads to the pedal without compromising the rider’s position.
*Keeping consistent contact with the bed of the shoe from heel to toe box without allowing the heel to rise early allows the rider to stay in his cycling position for a prolonged period of time by pulling backward through heel of the shoe rather than scraping the mud off the bottom of the shoe.
*Working this area will decrease the opportunity for the heel to turn outward. When it does this, the upper outer region of the soleus and calf can become dysfunctional.

2. Quads
*Maximize payload opportunity within the region while increasing flexibility so that the pelvis can organically shift with the rider’s torso allowing the back to flatten and the pedal stroke to take advantage of the pull/push through the center of the quads rather than pulling upward from the knee relying primarily on velocity.
*Decrease opportunity of adhesions (massage) allowing the muscles to fire independently rather than as one. Once all the muscles within the region stick together they are all going to increase the tension on their insertion points. Since they all attach in the patella tendon, knee problems can be avoided by rolling through these areas.
*Maintaining elasticity (massage) within this region allows the muscles to transfer wattage from the center of the quads to the center of the soleus as these are the most efficient transfer points of the pedal stroke.

4. Psoas
*Maximizing elasticity (massage) within this muscle will allow more force and flexibility to be accessed within the quads, lower, and upper back by using the stabilization of the saddle and associated core muscles.
*Decrease the pelvic tilt that detracts from allowing the pelvis to move naturally into a fixed static position desired for proper bike fitting.
*Maintaining the elasticity within the region reduces or eliminates the compression of the L4-5 region and the static weight placed on the hands. This allows the diaphragm to be open and allow the uptake of oxygen to be as efficient as possible.

5. Piriformis
*Maximizing elasticity (massage) within the glute region will allow efficiencies in power during 6-9 o clock in the rider’s pedal stoke. If you do notice a decrease in power within this region, your piriformis muscle will need to be addressed.
*Increase blood flow to the sciatic nerve region allowing the neurological feed to the lower extremities to be uncompromised.
*Maintaining elasticity(massage) within the glute region will allow the rider to maintain the use of the saddle as a platform for power. This platform allows proper functionality of the pelvis to occur, allowing the rider’s position to be consistent for a prolonged period of time without compromising the diaphragm, quads, or shoulders.

3. IT Band
*Maximize the efficiency of the surrounding muscles by creating additional blood flow (massage) to the IT band, which is a tendon. This will lessen the restrictions placed on the muscular fibers, thus increasing the range of motion and movement patterns in this region.
*Decrease the strain on the inner quad (VMO). When adhesions are present between the IT Band and Vastas Lateralis or Bicept Femoris, the rider may feel pain in the inner knee region. This is due to the IT band pulling the entire quad outward due to the lack of range of motion.
*Maintaining elasticity(massage) within this region will allow the knee to track properly behind the handle bar or in line with an elbow pad (Time Trial Position), not allowing undue stress on the piriformis muscle.

6. Pectorals
*Maximizing elasticity (massage) within the region is going to allow the shoulders to rotate back naturally, taking strain off the upper back and neck region.
*Arm reach to bars is more organic, and neurological feed to the hands is maximized by freeing up the nerve root within the pectoral region.
*Maintaining elasticity(massage) in this region will eliminate numbness in the hand, while also allowing the rider to sit on the saddle with proper weight distribution across the saddle. This will allow power to be transferred from the center of the rider’s back when the body is based on the saddle and transferred through the quads down to the pedal platform.

Now isn’t that ineresting?