July 16, 2010

AN EXPLANATION OF POWER TO WEIGHT RATIO & IT'S APPLICATION TO TRIATHLON

It is safe to say that one of the biggest buzz words in triathlon today is POWER. One of the more common ways of utilizing an athletes power data is in determining their power to weight ratio (P/W) during efforts, particularly climbing.

I've been studying this theory a lot the last couple months because I've been dropping a lot of weight, while also trying to gain power. I thought I'd share what I've learned.

So, what is the Power-To-Weight Ratio (P/W)?

Power to weight ratio is a fraction based on 2 variables: POWER (measured in Watts) & Weight (measured in pounds). The reason in determining & tracking ones power to weight ratio is to maximize its value to a specific task i.e.. running & cycling; not quite as much in swimming because of the buoyancy of the water.

Theoretically, a triathlete with a higher power to weight ratio will ride faster & climb hills better compared to a person with a lower Power to weight ration. Similar advantages apply to running. Some research has found that a runner can gain %1 in running speed for every %1 reduction in body fat.

For most triathletes one of the most simple & cost effective ways to get faster is to explore ways to increase your power to weight ratio.

The power-to-weight ratio is the power a person generates, divided by their body weight. Here's why this is important: Success in the sport of triathlon relates to one's ability to generate the greatest force & aerobic power, in the most economical manner, to overcome the drag or resistance of water, wind, or terrain.

You improve you power to weight ratio by becoming lighter & maintaining or increasing muscular strength. Being "lean & mean" is all about your power to weight ratio.

Utilization of a riders power to weight ratio is most commonly found when assessing their climbing ability. Let us assume there are 2 triathletes cycling who are of equivalent abilities with identical bikes, & components. Both cyclists will be climbing the same hill side by side at exactly the same time, the same day, under exactly the same conditions.

Rider 1 weighs in at 200 pounds & has an average sustainable power on the climb of 450 watts. Rider 2 weighs 150 pounds & has an average sustainable power on the same climb of 380 watts. If you were to base your opinion of each cyclists climbing ability solely on their power, you would believe that rider 1 would be able to beat rider 2 to the top. Granted, rider 1's sustainable power is 70 watts GREATER than rider 2's. (%15); however, power is not the only variable that counts for dragging themselves up a climb. TOTAL weight (body, bike frame, components, wheels, etc) also plays a role.

When we account for each rider, their weight in addition to their climbing power, we find that the power to weight ratio of each is:
Rider 1=2.25 watts/LB
Rider 2=2.53 watts/lb.
So rider 2 will get to the top of the climb first, even though rider 1 can generate %15 more power.

It would be hard to get rider 1 to lose the 10+ pounds needed to increase his power to weight ratio to that of rider 2 without losing power, and losing power would completely negate the reason to lose the 10+ pounds! What I & many more experienced athletes than I have found is that starving ourselves to attain our ideal triathlon weight can be counter productive. Although we might lose weight, figuring out where the weight loss occurred is the real question. If I am losing LEAN MUSCLE MASS, I am lowering my power output by cannibalizing the muscle that is generating my POWER!

Truth be told, well trained athletes have far more control over gaining power than they do lowering their body weight. By focusing my energy through training to maximize POWER, which increases lean muscle mass & can decrease overall body weight, both power & weight are optimized.

IMPROVING MY POWER TO WEIGHT RATIO:

Here are a couple workouts that can be implemented into a triathletes training plan to help improve their power output, & with improved power comes improved speed & climbing.

1) Big gear training. These "on the bike" big gear intervals. Can be done on the road with a gradual climb or on the indoor trainer. You will push the big gears so that your average cadence is between 50-60 rpm, staying seated & concentrating on a smooth circular pedal stroke throughout the set. Intervals should last between 5-10 minutes, with recovery being half the interval time.

You can actually do big gear training for the run too. I learned this little trick from Barbara ("Barb") Metz Lindquist while at the USAT coaching seminar in 2006. Tie an old mountain bike tube around your hips/waist, tie a rope to the tube, and then tie the rope around an old car or truck tire. Then run & pull the tire while leaning forward at the ankles. The pressure of the tire pulling backwards on your hips will force you to pull your hips forward, which is proper run form, while also giving you the same benefits of big gear training for the run. A few hints for this run specific exercise,
A)keep your foot cadence high. Don't make your foot rpm's slower like you would if you were cycling.
B)DO NOT LEAN forward at the hips! That is poor running form! Practice leaning forward at the ankles & pulling your hips forward & lightly up as if you are stopping at the end of a pelvic thrust.
C)lower the duration of the intervals by half of what your doing for the bike.

2) Climbing. These are the crème-del-a-crem for triathletes looking to improve their P/W. These should be performed on long gradual climbs at cadence between 75-85 rpm. Stay seated. Recovery should last the time of the climb. Try & get your heart rate to 85-90% of your max effort, also called zone 5 if training by lactate threshold.

Again, you can do hill climbing for the run also, just make sure to lean forward at the ankles, & not the hips.

3) Weight lifting & core work. I'm going to go into more detail about weight lifting because weight lifting has received a bad rap by a lot of endurance triathletes, cyclists, & runners. Weight lifting increases muscle power in 2 ways: the more muscle you have the less effort it takes to produce a given power, & strength training trains your muscles to reproduce energy quickly so they don't tire as fast & can recover from short bouts of high intensity movements, like climbing or passing another triathlete. Energy production is achieved deep down in the muscle fibers, where the stores of glycogen, enzymes that increase the speed of muscular contraction, & stored creatine phosphocreatine are all increased because of strength training.
Increasing muscular strength increases muscular endurance. When you have more muscle to draw on it takes longer to wear out. I.E., if you find that you sometimes reach muscular fatigue before you reach cardiovascular fatigue, then you should increase your muscular strength so that you can have more in reserve. Endurance training decreases cardiovascular fatigue; strength training increases muscular endurance, which in turn decreases muscular fatigue.

From what I have researched, the optimal body fat % for triathletes is %4-10 for men, %10-15 for women. If your body is way out of these ranges you have the greatest opportunity for improvement.

If your going to try & drop body weight to increase you power to weight ratio:

-lose the weight slowly, eat small frequent meals, & avoid low protein, low fat, or low carb diets. Moderation is the key.

-Get your body composition checked every 4-8 weeks. If your losing lean mass you need to adjust your diet The most common way to get your body composition tested is the caliper measurement method. For this you must have the same person check you for consistent measurements. Accuracy (hence consistency) is based on the experience/skill of the tester, & measurements taken in the exact same location. A good tester will have the ability to compensate for various skin thickness & pliability. A good option for most triathletes is to find an experienced tester that uses calipers.

Water weighing measurement method, which is the dunk tank. This method tends to be the standard that all other measurement tools are compared to.

It's going to take time to make changes to your body composition; be patient. Some triathletes seek guidance from a sport dietitian for determining how much you should lose while maintaining energy levels to train well. A professional can provide some insight on how much weight you can realistically lose to assist you in reaching your goals.

Decreasing your body fat while maintaining lean mass, and the energy to carry out triathlon training, will take some planning. Most feel that decreasing your calories by 200-300 per day is a conservative, but smart, approach to fat reduction.

Remember that the quality of food matters. A serious triathlete will meet daily carbohydrate needs
with a variety of nutrient-rich foods. Avoid more processed foods. Protein should come from low saturated fat meats or plant sources such as soy beans or other legumes. Healthy fats from olive oil, flaxseed, nuts and avocados are a few good options. Avoid high sugar/calorie beverages (fruit juice blends, sodas, sports drinks) at and between meals. Go with low-calorie beverages to meet your hydration needs. Reserve the sports drinks and bars for use during training.

I have found I get MUCH BETTER results at building strength & losing fat when I take a protein supplement, multi vitamin, vitamin E, vitamin C, fish oil, & glutamine immediately before bed, as soon as I wake up, & immediately after workouts. Prevents your body from cannibalizing it's muscle stores.

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