Aero Helmet Wind Tunnel Testing

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We tested several aero helmets. Not surprisingly, we found that every athlete responds differently to aero equipment. One common theme is that there were “good” and “bad” helmets, regardless of the rider that was testing them. Results for the Louis Garneau and Giro are shown above. Surprisingly, the old Troxel titanium dimpled helmet also tested well.
  • Lower profile helmets are more aerodynamic
  • Shape matters, the helmet should transition to the rider’s back as seamlessly as possible
  • Visors were not tested – may or may not have an impact
  • “Filled” tails were not tested – again, may have an impact especially for tails that sit up off the back
We also tested three hand positions, the “pointer”, “pistol”, and “superman”. What was apparent is that there were little discernible differences in the results, with the best result from the original baseline “pointer” position. This is likely due to the smaller frontal area that the position provides, as compared to the other two positions.
  • All three hand positions are fairly close in terms of aerodynamics
  • Gloves were not tested, however if gloves were to be worn, a low profile set such as the aero versions from Castelli or Nike should be considered
  • Smaller hand profiles are important

How to Calculate Cycling Aerodynamic Drag Using a Power Meter

Originally seen at http://cyclingillustrated.com/how-to-calculate-cycling-aerodynamic-drag-using-a-power-meter/

Don’t have access to a wind tunnel or velodrome? No problem. You can test your own time trial position or gear/helmet changes using the following instructions. All you need is a calm day, an uninterrupted flat course, a power meter, and the following instructions. Using details in the screenshot image above, and the calculator provided by Analytic Cycling, you can estimate the power required to complete a time trial for any specific time. In the example screen shot, I used a 20k time trial at sea level on a calm day. An alternative method for estimating aerodynamic drag can be found by measuring anthropometric data.

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The calculators and links required are located at:

For this example, rolling resistance for the course is in the numbers in the screen shot. For purposes of the estimate, use the defaults in the image for pedal range, wind, drag, air pressure, Crr, and rise.

Then plug in your crank length and average cadence.

Also plug in the speed in meters per second, then change the frontal area up or down until the power matches the average from the race, with the caveat of the time lost to inertia at the start (add 5 seconds to the time).

An example for a hypothetical “aero-tuned” cyclist competing at the San Diego Time Trial at Fiesta Island, which is a point to point 3-lap 20k course:

  • .44 frontal area [.440m^2 x 0.5 = .220m^2 of CdA]
  • 83kg rider and bike Slope – 0.0015, crr 0.004, 12.69 m/s – 332w – 26:15 for 20k
  • + 5 secs first lap = 26:20

  • .44 frontal area [.440m^2 x 0.5 = .220m^2 of CdA]
  • 83kg rider and bike Slope – 0.0015, crr 0.004, 12.82 m/s – 341w – 26:00 for 20k
  • + 5 secs first lap = 26:05

Once you know your CdA, you can calculate your Functional Threshold Power (FTP) as it relates to your aerodynamic drag (CdA) in terms of W/m^2. With this number you can then compare your aerodynamic drag/power ratio to other riders.

Racing a Time Trial: Preparation, Strategy, Recovery

Originally seen at http://cyclingillustrated.com/how-to-prepare-for-a-time-trial-part-1/

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It’s the day before the big event, and you are wondering “should I take it easy today?” Yes, absolutely. One of the most important race preparation elements is relaxation. You should arrive at the event relaxed and prepared to give your best effort. The goal is to line up the day of the event in the most rested and best prepared condition possible.

How to best prepare yourself depends on where you are starting from and the type of event you are competing in. There are a few basic preparation tasks that I use for time trial races:

  • Prep-ride warm up the day before. I’ll use the same 40 minute warm-up the day before the event as I do on race day, and if I can I will ride the actual race course. The goal here is to blow out the cobwebs while staying relaxed and fresh.
  • Confidence and mental rehearsal. If this is a new course, or a championship event, completing a pre ride the day before on the actual course will give you confidence to corner at the maximum possible speed, and will allow you to observe the course profile and any potential hazards. Practice mental rehearsal of a strong start, smooth turnaround, and solid finish. Visualize yourself pedaling smoothly with relaxed breathing.
  • Nutrition and sleep. I tend to keep nutrition simple and stick to my normal diet. I will not restrict calories the day before a race and I tend to avoid heavy foods that may cause digestive problems. Since many events begin in the morning, it is important to turn in early to prevent unnecessary fatigue. I strive to get 7.5 to 8 hours of sleep the night before the event.

Warm Up

The key to the warm up is to properly prepare for the race while remaining rested, relaxed, and by staying cool. The following warm-up is 40 minutes total, completed on a trainer or on rollers.

Start with a 20 minute easy spin, slowly raising cadence to 100 rpm, and include a few 5 second high-cadence bursts, then:

  • 1×4 minutes @ 90%/95%/100% of FTP w/2 minutes easy spin between intervals 1-2, 2-3, then after interval
  • 4 minutes easy spin
  • Roll over to the start area with 10 minutes to go

Strategy for Pacing a Time Trial

Racing a course that has rolling climbs can necessitate a slightly different strategy. Pushing (a little) harder on the climbs, and letting off (a little) on the descent can prove to be a faster strategy than to iso pace the rolling event. In contrast, I prefer to pace evenly or just slightly harder into a headwind and either even or slightly easier with a tailwind, providing that I am riding directly into the headwind. Pacing a time trial is an acquired skill, one that will likely take you several events to master. Using your power meter to pace in training is an excellent method of calibrating your perceived exertion for race day.

For flat and low wind time trial races of durations between 10 miles and 40 kilometers, I often break the event into four parts.

The Start House

Rolling a good start will lay the foundation for a confident race. With five minutes to go you head over to the start area and take your position in line. You spin the cranks forward and ensure that you are in the correct gear. Your cycling computer is ready to record. You are hydrated, rested, warmed up and ready to compete. Close your eyes and picture yourself on the podium. Draw a mental picture of yourself rolling across the finish line as you clock a new personal best time. Find your motivation and remember it for later. After climbing up to the start house, or the start line, ensure that you have shifted to a large enough gear that will allow you to start out of the saddle and power up to speed for 10 seconds. At 1 minute out from your start, hit your timer. Take a few calm deep breaths and prepare for the countdown. Go time.

The First 5 Minutes

This is one of the most critical sections of the race and pacing this section correctly can mean the difference between correctly pacing your best effort and blowing midway through the event. Pacing with a power meter can be invaluable during these first minutes. Your power during this period should put you in the range of 95% of your projected average power for the race. After the five minutes you should take inventory on your perceived exertion as compared to actual power, and adjust as needed for the day. Not everything is black and white when it comes to pacing with power. Use your power meter as a gauge, deferring to your perceived exertion. Listen to your breathing, focus on a smooth cadence. Push it. Head toward the turn-around.

The Turn-Around

If you are on an out-an-back course, you’ll want to know how to best approach the turn-around. As you head out to the turn-around, after the first five minutes of the event and after you have settled in to a strong sustainable rhythm, try to ramp it up a little harder and keep yourself focused on riding the razor’s edge. This period of the race is very challenging to pace, as you are still relatively fresh yet you may have doubts about your starting pace and your ability to keep your current pace up for the duration. “Every second counts” and efficient time trial turnarounds can lead to quicker TT times. Practicing turnarounds can also lead to more confident bike handling. In the off season I practice the following routine on a closed street with a road cone. I’ve found that the fastest way to navigate a turnaround is to

  • Approach the turnaround as far to the right of the course as you can ride
  • Keep your speed up until the very last moment
  • Shift up two or three cogs, then sit up and get on the brake hoods
  • Brake, pass the cone by one meter, look over your left shoulder, then begin to corner
  • Scrub just enough speed to corner and take a tight line with the cone on your left
  • Sprint back up to speed, out of the saddle
  • Get back up to speed quickly and then get back into the aerobars
  • Shift down and quickly settle into your TT pace

The Finish Line

This is the “perceived longest” and most challenging section of the race. This is the section where you make deals with yourself in order to finish strong. “Just steady to the next mile marker” … “ok, keep this effort until you pass the next rider”. This is where the hours of intervals and time spent training and racing on your TT bike will pay dividends. Metering is done by perceived exertion using your power meter as an additional gauge. Your comfort during this section of the course can also play into how focused you are on putting out as much power as you possibly can. You may find yourself shifting around on the saddle, or unable to hold your position. You will have to dig deep into your well of confidence. Remember your motivation. Give our all and leave it all out on the course, punching across the line with everything you have left in the tank.

Post-Race Recovery

Recovery after a time trial and after challenging workouts is undoubtedly one of the most important aspects of a well-rounded training program for the competitive cyclist. Day and day out training, work, home, and life stresses can increase the fatigue that a rider experiences throughout the day, and can minimize the effectiveness of the workouts performed. To realize the most of your training program, effective recovery techniques can lessen the stresses of daily life and can help to prepare you for the next day’s workout.

A few of my favorites include:

  • Nutrition – replace glycogen with a sports drink within 30mins-2hrs post ride at the rate of 1.5g carbohydrate per kilogram of body weight per hour for up to 4 hours. I prefer a bottle of Fluid, a Coke or bottle of Cytomax.
  • Clean up – shower, or after a race/training ride where I cannot immediately shower, I’ll use a few baby wipes to clean up.
  • Baby powder – keeps things dry.
  • Nap – a short 20-30min lunchtime/afternoon nap can be beneficial.
  • Stretching – improves mobility, flexibility, eliminates stiffness.
  • Massage and Compression socks – massage is worth it if you need work done. Also, “the Stick” and Foam roller work well.
  • Ice – if I am feeling particularly sore, I’ll ice my joints and/or muscles immediately after a ride.
  • Hydrotherapy – a warm bath can work wonders for a sore body (however, not immediately following a workout).
  • NSAIDS – Advil/etc. can help with pain, but use sparingly and as directed by your doctor, stomach ulcers and other risks are involved.
  • Sleep – aim for 8 hours per night, no more than 9, no less than 7.5 ~

Compression clothing can help with recovery, as well as office workers, travelers, and those who spend considerable amounts of time standing throughout the day. Mid-day stretching and “sunshine breaks” can also assist with reducing stress in the workplace. A healthy diet and ample vitamin supplementation are important foundations for a sound training program.

The 10-Minute Cycling Core Maintenance Plan

As seen on CyclingIllustrated.com  http://cyclingillustrated.com/category/gary-tingley/

Let’s face it, core work is often overlooked and many riders avoid it altogether. It can be a hassle to find time to incorporate it, and with so many variations, where do you start? What if a simple, 10-minute, daily routine could prevent future overuse and back strain problems, increase your balance and stability, and make you an all-around better cyclist? Seems like a no-brainer, right? We know that the days are getting shorter and the weekend mileage is increasing with off-season base work.

Now is the time to make a commitment to a simple core strength training routine. Don’t be a victim to back strain and injury this off-season. A simple routine such as the one below, done each morning, will help to ensure that you remain injury free. Note: As a warning, before beginning any new exercise/conditioning program you should first consult your physician, trainer, or coach. So here it is. 3 exercises in 10 minutes. Simple but effective.

Start with: Side Plank
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Lie on your side on the mat. Now place your forearm on the mat under your shoulder, perpendicular to your body. Stack your upper leg on top of your lower leg with your feet together. Straighten your body and begin to raise your body upward until straight and in a line. Hold the position for 30 seconds, relax and then repeat with the other side of the body, completing 3 x 30 seconds efforts for each side. Then turn to face the mat and relax for 30 seconds, with both hands and knees on the mat.

Next: Bird Dog
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Place your palms and knees on the mat. Extend your hand in and outward stretch and well as the opposing foot. Hold the position for 30 seconds, and then repeat with the other hand and foot, completing 3 x 30 seconds efforts for each side of the body. Then relax for 30 seconds and return to both hands and knees on the mat.

Finish with: Front Plank
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Place your forearms on mat, with your elbows under your shoulders. Position your legs together with toes touching the floor. Raise your knees and body upward by straightening your entire body in a line. Hold the position for 2-3 minutes. Then relax for 30 seconds and repeat 2 or 3 additional times. This exercise increases core strength and will result in noticeable abdominal definition.

3 Ways to Boost Your Fitness This Winter

3 Ways to Boost Your Fitness This Winter (pdf article)

as seen at https://issuu.com/cyclingillustrated/docs/cyclingillustrated_issue2_issuu/60