Bodybuilding.com - Cycling Equipment: Just Do It... Right!

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Christine is a world-class duathlete!

Why would any athlete, competitive or recreational, compromise proper body mechanics to simply save time or money? This should not even be an option. Nonetheless, I sit here, guilty as charged for that exact error in judgement...

By: Christine Knight

I would know better.

Perhaps I didn't want to spend the cash on a proper fit, nor clear four hours in a day to do things right. I have clients to take care of... my needs can wait. Besides, the body will always adapt to its environment, right? Oh, can I be more wrong?

I am first in line to confess making minor mistakes in training and races. This is how we learn and improve. But when significant errors can be avoided altogether, take the steps to do so. In detail, my misconception began with a tri-bike purchase two winters ago.

Proper Bike Fit

Fit Calculator

Enter your inseam measurement below and click calculate.

How To Measure Your Inseam

Stand with your back against a wall, your bare feet 6" apart on a hard floor, looking straight ahead.

Place a book or carpenter's square between your legs with one edge against the wall, and pull it up firmly into your crotch, simulating the pressure of your saddle while riding.

Have a helper measure from the top edge of the book to the floor, in centimeters or inches.

Repeat two or three times, for consistency, and average the results to get your inseam length.

Determining Your Frame Size

Frame size refers to the length of the frame's seat tube. Frames are measured along the seat tube in one of two ways, center-to-top (C-T) or center-to-center (C-C). C-T measures the distance from the center of the bottom bracket to the top of the top tube or seat lug (See image below).

C-C measures from the center of the bottom bracket to the center of the top tube. Since C-T measures to a point higher on the frame, a frame measuring 55cm C-T would also measure roughly 53.5–54cm C-C, a difference of 1–1.5cm.

To size your C-T road frame, we use a guideline of .67 x inseam length. For example, if you have an 85cm inseam, your C-T frame size would be .67 x 85cm, or 57cm.

LeMond's formula establishes C-C size by the formula .65 x inseam length, which yields virtually the same frame size when you add the 1–1.5cm difference between C-C and C-T.

Larger riders (6'0" and up) may find that this formula puts them on a too small, and uncomfortable, road frame. A taller cyclist who wants a more comfortable frame may be better off selecting a frame 27–28cm less than inseam length, C-T.

For a mountain bike, we start by recommending a frame in the range of 10–12cm smaller than you take in a road frame. For example, if you ride a 55cm C-T road frame, look for a 43–45cm (17–18") C-T mountain frame.

Frame Dimensions
A1 Seat Tube Length (C—T)
A2 Seat Tube Length (C—C)
B Top Tube length (C—C)
C Stem Length (C—C)

In many ways, though, it is more important to fit a mountain frame by the top tube length needed, rather than by the seat tube length. For instance, you might be able to get to the proper frame clearance, saddle height and neutral knee position on either a 17" frame or a 19" frame. Yet the 19" frame will likely have a top tube 1" longer than the 17" frame, which changes your stem length accordingly.

Or, one manufacturer's 17" frame may give you a 22" top tube, while the next one's 17" gives you a 22.8". More on this below… just make sure that you'll be able to work out your top tube and stem length for a given frame.

Determining Your Seat Height

With the right frame size, you'll be able to set your correct seat height, which will be within a centimeter of .883 x inseam length, measured from the center of the bottom bracket to the low point of the top of your seat. This allows full leg extension, with a slight bend in the leg at the bottom of the pedal stroke.

LeMond recommends that you then shorten this length by 3mm when using clipless pedals. Also, you might consider a slightly taller seat height if you ride with your toes down and your heel raised. Most importantly, make any changes in seat height gradually, and give your body time to adapt to the new position.

Going by basic charts, I fell between sizes. Without seeking professional opinion, I chose the larger frame figuring it would do the trick. I spent two race seasons going from injury-free to frustrating bouts of swollen knees, back spasms, hip soreness and an adductor longus pull. Not all were necessarily created by the wrong bike fit, but you can bet this didn't help. It took a fellow athlete at the last championship event to convince me the frame was far too large.

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So upon returning home, I was on Ebay to sell one bike and shop for another. The difference this round was I spent time having a local dealer pre-fit me so there was no question on frame size. Upon receiving a new Giant, I spent the time and cash to have custom fitting achieved. As I increased mileage on a lighter, more comfortable frame, my physical ailments disappeared.

A Dollar Amount On Your Body?

You can't put a dollar or time constraint on your body. Period. I found this out the hard and painful way. Think of all the time I wasted nursing avoidable injuries, not to mention my mediocre bike splits.

Take the A-profile races such as a World Championship... proper equipment fit could mean the difference between top ten and bottom quarter. It's all part of the equation, which doesn't stop at just the bike.

Conclusion

Whatever your sport, all equipment must be properly fit. Whether it's a helmet, goggles, shoes, uniform... you wear it, you fit it. Do not compromise.

Would you spend six months training for a strongman competition and show up wearing shoes that are two sizes too small, limping through the Atlas Stone event or painfully planting feet for a clean and press?

You may as well congratulate the guy next to you, hang up your weight belt and go have a pint. Spend the time (and yes, money) to do it right from the start.

Experiment, research and seek professional guidance when needed. Find what works for you and stick with it. This all comes down to self investment. Don't short change yourself. You are so worth it!

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