Why run ultramarathons?

I've been asked many times "why run ultras?" and spent many hours thinking about the answer, especially towards the end of long races. There is no good answer, but here are a selection of possibilities http://fellrnr.com/wiki/Why_Run_Ultras

 

When I first started to write about the "why" of ultrarunning, I thought that would be two or three possible answers, but over time the list has grown far longer. I've had lots of input and suggestions from many runners, and I welcome further suggestions.

Running Cadence Update

Cadence (how often your feet land) is one of the most critical aspects of running as it can reduce the likelihood of injuries and improve running economy (how fast you run). I've refreshed my page on running cadence to improve clarity, and I've included some more scientific research I found while looking into running economy. 

The update to running economy is taking much longer than I expected as there is a huge amount of research, some of it conflicting. How shoe weight and ground contact time effects running economy is particularly confusing.

Best Hydration Systems

Here are my recommendations for hydration systems, based on my evaluation for running the Keys 100 and Badwater.  (Remember, drink to thirst as overhydration can be fatal.)

Garmin Fenix 2 - Buyer Beware

I've downgraded my review of Garmin's Fenix 2 to "buyer beware" due to the GPS accuracy problems. I've also updated my GPS testingresults with details of the 620 without EPO data and the Fenix 2 without WAAS enabled.

TomTom Cardio GPS Accuracy testing

Final GPS accuracy results for the TomTom Cardio published at http://fellrnr.com/wiki/GPS_Accuracy

DIY CoolSculpting: 2 Years On

Removing body fat with ice seems too good to be true. How well does it work, and how long does it last? Here's my update 2 year after my DIY CoolSculpting experiment. http://fellrnr.com/wiki/CoolSculpting