Tuesday, March 31, 2015

Shimano Polymer cables

Since using the Shimano hidden cable system, which is designed to be more aerodynamic and give a generally cleaner look, I’ve had to replace the derailleur cable and housing every 1.5 to 2 years. Due to the sharper bends it causes a little more cable resistance and any breakdown of the cable and housing increases the resistance of shifting to the point it's really a pain to modulate the shift normally. The traditional higher end Shimano cables are PTFE coated which work great initially but eventually the "coating" wears off and accumulates inside the housing and causes increased friction and hard shifting. I guess it kind of balls up. Sean at Brookfield bicycle center recommended Shimano's newer cable and housing system for Ultegra 6800 and Dura ace 9000 that has a polymer coating that will not ball up inside the housing. Shimano also coats the inside of the cable housing with a silicone grease for added "slide". I decided to change only the rear derailleur cable and housing as every else is working well.

Overall summary:
This cable system is honestly amazing, shifting modulation is better now than when the bike came new with Jag wire cables. The polymer coating ensures extremely smooth lever movement. These cables are so slick that If you use these on the braking system it's recommended you scrape off the polymer coating where the cable anchors to the brake caliper fixing bolt as it's so slick it can slide past the fixing bolt, that’s how slick it is.
The Ultegra version of the polymer cables

You can see the actual polymer coating on the cables.
The redish coating can be scraped off where the brake anchor
clamps down as to prevent the cable from slipping loose. 

Saturday, March 21, 2015

Pacing and VO2max

 The percentage of VO2max that you can sustain for a specific amount of time is predictable.  For example, research has shown that 100% VO2max can be sustained for only about 8 to 10 minutes.  The longer the race, the lower the percent VO2max at which you’ll run it.  Talented, elite runners race a 3-K at about 98 to 100% VO2max, a 5-K at about 90 to 95% VO2max, and a marathon at about 80 to 85% VO2max.  Just like sustaining LT pace, the faster you are, the higher the percentage of your VO2max that you can sustain for a specific distance.  Therefore, the above percentages will be lower for average or below-average runners.

Wednesday, March 11, 2015

Hyper and Hypo conditioning in cycling

The offseason is the perfect time to focus on correcting muscular imbalances as well as flexibility. Cyclists are notorious for isolated hyper conditioning and deconditioning in certain muscle groups due to always performing in a sagittal plane (toward the front). Major areas are hyper development of the quadriceps and glute muscles with chronic under development of the low back and abs as well as varying levels of deconditioning of the abductors and adductors. Abductors and adductors are largely responsible for frontal plane movements (side to side) but add stabilization to the overall lower body and assists in keeping your motion or mechanics correct. They also remove strain from surrounding muscle groups that would have to over compensate for the deconditioned areas. If anyone's fitness routine or sport is continually worked in the sagittal plane the frontal and transverse plane muscles become deconditioned thus affecting the body’s ability to function properly in a triplanar fashion eventually resulting in injury.