Evaluation of PowerCranks as an Effective Training Tool

1. Evaluation of PowerCranks as an Effective Training Tool Michael Durner MS, CSCS USA Cycling Certified Coach

2. Pow, Pow, Powerwheels • History • Description • Evaluation • Efficacy • Cost/Benefit • Safety • Recommendation • References • Questions

3. For Your Viewing Pleasure • PowerCranks intro

4. History of PowerCranks • Designed by Dr. Frank Day, finisher of 1st Ironman Triathlon • Originally for use in vehicle to set human powered land speed record

5. History of PowerCranks • Only about 1% of all cyclists are able to utilize entire pedal stroke for power production (including pros) • Day realized that PowerCranks could be an effective training tool for cyclists and triathletes

6. Description • Using a one-way clutch in each crank arm allows them to move independent of one another • Crank arms will not return to the 12 o’clock position unless actively moved through all 360 degrees of rotation

7. Description • Rider is essentially performing single leg drills with both legs simultaneously for the entire ride • This forces the use of hip and knee flexors which are usually passive while riding

9. Evaluation • Efficacy • Cost/Benefit Ratio • Safety

10. Efficacy • In a study from KU, a group that trained with PC for 6 weeks saw improvements in heart rate, O2 consumption and gross efficiency over pretraining tests • The PC group’s heart rates were also significantly lower than the non PC group with identical training plans and similar pretraining values (Luttrell & Potteiger, 2003).

11. Efficacy • Over an 8 week period, Exercise Physiology Professor, Dr. Stephen Cheung saw the following result from using PowerCranks • 8% increase in power index • Heart rate at pretest lactate threshold wattage was 8 – 10 bpm lower in post test • Lactate Threshold 15w higher in post test

12. Efficacy • “The damn things actually insist (it’s easy to attribute will to these things) that you pedal properly in order to get power and pedal efficiency… (Howard, 1999)” • Without a doubt the finest tool available for learning a better pedal stroke are PowerCranks…they bring results faster than any other training technique that I am aware of. (Demerley, 2001)”

13. Efficacy

14. Cost/Benefit Ratio • “These cranks may seem expensive, but they are worth it in terms of the results you get and how fast you get them. If you use them you’ll get faster, fast.” (Demerley, 2001) • Retail Price = $790 US

15. Safety • All sources recommend starting on a stationary trainer • Less experience = more time on trainer • Steep learning curve for climbing out of the saddle • Not for mountain biking or technically demanding road situations

16. Recommendations • Positive results of evaluation • Definitely recommend them but with stipulation based on athletes’ goals and ability level • Still plan on performing a self evaluation and possibly a more in depth training study

17. References • Burke, E. (2002). Serious Cycling, 2nd ed. Human Kinetics, Champaign, IL • Cheung, S. (2005). “PezCranking: PowerCranks Baseline”, Pez Cycling News. Pezcycling.com • Crawford, R. (2002). “Tune up your Efficiency.” Bike.com • Demerley, T. (2001). “Get Fast, Fast.” Xtri.com • Golich, D. (2005). CTS Premier Coach. Personal interview. • Horowitz, J. (2004 – 2005). “PowerCranks Training Diary”, Pez Cycling News, Pezcycling.com • Howard, J. (1999). “CUTTING EDGE The Power that Spanks,” Triathlete. Sept. 99 • Howie, C. (2005). Head Coach: Howie Endurance Project. Howieendurnaceproject.com • Larsen, B. (2003). “PowerCranks: Crank it up.” Cyclingnews.com • Luttrell, M., Potteiger, J. (2003). Effects of Short-Term Training Using PowerCranks on Cardiovascular Fitness and Cycling Efficiency. Journal of Strength and Conditioning Research 17(4), 785-791. • Manantan, C. (2002). “PowerCranks Product Review.” Pez Cycling News, Pezcycling.com • PowerCranks.com • Zinn, L. (2005). Tech Report. Velonews, Velonews.com

18. Questions????