Archive for July, 2012

A bike comes complete with 2 wheels, a handlebar, a seat and 2 pedals. You would think that’s all there is to it. Not when it comes to discussing triathlon bikes! Each piece can be replaced with something specifically designed for peak performance. The amount of money that you can put into your bike can be astronomical! Let’s just look at the pedals.

To know what kind of pedal is best, it is important to understand the pedal stroke. Because of the design of the bicycle, the strongest push is on the downstroke. But that is only 25% of the pedal stroke. If you can increase the push on the other 75% of the cycle, theoretically, you will have a stronger stroke, and the bike will be propelled faster.

The 4 parts of a pedal stroke are the down stroke, back stroke, up stroke, and forward stroke – in that order.  As mentioned earlier, the down stroke is the strongest part, as you are using the large muscles in the front of the thighs (quadriceps) and butt (gluteus maximus) to propel the pedal down. This stroke becomes even stronger when you stand on the pedals to push down.

Even with traditional flat pedals, it is possible to increase the strength of you back stroke and front stroke, using a technique called ankling. Ankling is the action of raising or lowering your heel to change the angle of your ankle compared to the ground. If you raise your heel during the back stroke, you push the pedal backwards, increasing the strength of the stroke. Likewise, lowering the heel at the top of the stroke will push the pedal forward. This relatively simple (in theory anyways) should increase the speed of the bike, by making your pedal stroke smoother and consistent.

The backstroke primarily uses the hamstring muscles in the back of the thigh. Start the downstroke between the 3 and 4 o’clock positions of the pedal circle to make it more efficient. Continuing to push down to the bottom of the stroke wastes energy, as the pedal is not actually moving down at the 6 o’clock position. This effectively gives the quaddriceps and gluteus muscles a tiny rest in every stroke.

Pulling on the upstroke requires some sort of system that attaches the foot to the pedal. Again, if you are able to work through the entire stroke, instead of resting on the upstroke, you have more power to move faster. The upstroke uses a different set of muscles, again – The hip flexors. By allowing different muscle groups to work at different parts of the pedal stroke, you are reducing fatigue and increasing the distance or speed at which you can ride. Even if you don’t need to increase the power of your stroke, lifting the foot slightly on the upstroke decreases the weight that the opposite foot needs to move on the downstroke.

http://triathlonresource.com/index_files/Page2937.htm

So which is better, clipped-in or clipless pedals? Clipless pedals provide an additional safety feature compared to toe clips and straps. Your foot will disengage from the pedal by twisting your foot slightly. With toe clips and straps, your feet may come out of the pedals if you fall, but they may not. Clipless pedals also increase pedalling efficiency by allowing the orientation of your foot on the pedal to change slightly, making movements optimum.

http://university.tri-sports.com/2011/09/09/beginner%E2%80%99s-guide-to-clipless-pedals/:

The cost: Toe clips at Mountain Equipment Coop (MEC): $8 for plastic ones with nylon straps, $14 for metal clips with leather straps. Reviews say that the plastic ones are better.

Clipless pedals: Anywhere from $30 to $411 at MEC. And then you need to buy the shoes!

For a beginner triathlete, the expense of clipless pedals may not be worthwhile. I the meantime, I will try to develop a strong back stroke on my flat peadals, and put toe clips on my Christmas wish list!

Weights and Measures

Posted: July 20, 2012 in Uncategorized

Often, when people start on an exercise program, or a fitness program, they use their weight and waist size to monitor their progress. While this is technically not an exercise or fitness program, it may still be tempting to use weight and measurements in my progress reports.

Findings from a study published in the journal Circulation,  which looked at almost 14,400 middle-aged men and then tracked them over 11  years found that those who became more fit during the study period (as measured by aerobic  intensity test on a treadmill), or those who maintained their fitness were at  lower overall risk of dying from heart disease or dying from any cause. This was true even if their weight stayed the same or went up, compared to  men whose fitness levels dipped over time. Lead researcher Duck-chul Lee said in a statement “You can worry less about your weight as long as you continue to maintain or  increase your fitness levels.” This study examined men who were at an acceptable weight, or slightly overweight. It did not study obese men. Read more: http://www.ctvnews.ca/fit-vs-fat-which-matters-more-for-a-long-life-1.737104#ixzz217aBpZTV

A study done in Minneapolis in 2008 found that regular weight monitoring in obese adults did encourage weight loss. http://www.ncbi.nlm.nih.gov/pubmed/18976879. A previous study in South Carolina in 2005 came to the same conclusion: regular monitoring encouraged weight loss. http://www.ncbi.nlm.nih.gov/pubmed/16242064.

This discussion of what motivates people to learn or change has been going on in our school systems for quite a while. In that setting, the decision is to assign a grade, or to write an evaluation. More and more schools, including colleges and universities. are finding that objective evaluations provide just as much or more motivation to students to learn. http://www.npr.org/templates/story/story.php?storyId=4618720&sc=emaf and http://www.insidehighered.com/news/2009/01/22/grades#.UAREd11JZzY.email.

In the end, there is always a measurement of some sort. Whether it is a University scholarship, landing a job, a personal best, or a gold medal, it is up to the individual to decide what motivates them and find the areas that reward those things.

As organizations, schools and individuals, we need to recognize that different people have different motivators. We need to provide rewards for a variety of motivators in order to have a balanced society, productive workers, happy students, and fit athletes.

There has been a lot of interest in barefoot running these days.

In 2010, Christopher MacDougall wrote “Born to Run” about the Tarahumara Indians of Mexico’s deadly Copper Canyons who run hundreds of miles at a time – barefoot. He has looked at the biomechanics of the body and come to the conclusion that anyone can run – you just have to know how! (http://www.chrismcdougall.com/) I have not yet read the book, but it is on my list.

Very generally, the thought is that shoes are not natural. We are born barefoot, and that is the way we are intended to walk and run. Most people in developing countries run barefoot all the time, and don’t have the same kind of injuries that the developed world sees. Shoes should only be worn to protect your feet from cuts from stepping on things, not for support.

What is the difference between running with and without shoes? As I understand it, when running in shoes (traditional runners), the heel strikes first and then the foot rolls forward to push off of the ball of the foot. The hard heel-strike causes pressure up the leg to the knee. Runners, therefore, are made with more cushioning in the heel, to minimize the damage. When running barefoot, the middle of the foot strikes first. This allows for cushioning of the strike, taking pressure off of the heel.

The term “barefoot running” may be misleading. It is possible to run a barefoot style while wearing shoes. The shoes do not need to be the heavy runners traditionally worn for running, but can be a lighter, minimalist type of shoe. This has, of course, sparked the development of new lines of expensive “minimalist” shoes! The Barefoot Shoe store (http://www.borntorun.com/) has a whole line of light running shoes, but Vibram seems to have the monopoly market on the Five-fingers “glove” for the feet (http://www.vibramfivefingers.com/).

All I know is that my knees and hips will not tolerate my previous running style, and my daughter has used “five fingers” for a week, and her feet are already noticeably stronger. While I will not spend the money on the five-fingers minimalist shoe, I will try to develop the style of barefoot running in lighter shoes.

These are the shoes my 12 year old runs in