Juergs has been training in fivefingers since 2006 when he got his first pair of VFF Classics. Since then, he’d picked up some blue camouflage KSOs. Most recently, Juergs grabbed some of the new fivefinger KSO Treks to use them for his first (pseudo)barefoot ultra — a race he’s running this Sunday! Good luck on your race!

Since the Treks are so new, I asked if Juergs would share a few words about how the Treks were performing in his training and he graciously accepted. Below are his photos and running reports:

First impressions of the KSO Treks

First, I got my size 43 on Friday 18th from Summit Hut:

Ah the pristine soles of a brand new pair of Vibram fivefinger KSO Treks.

13 mile trail run 9/20/09

I will be doing a 50K Ultra Trail Race on October 4th and this is the main reason for purchasing the KSO Treks. I have pre-run most of the course and around mile 20 spirits get low from all the stone bruising. I have been running Barefoot since 2006 so the pain is nothing new.

The course features rolling hills, flat stretches, and a killer hill. Almost 300’ of elevation gain in less than 1/2 mile will reduce most folks to walking. We see this hill again on the way back, and the climb is even harder. The course is 60% dirt trails, 30% rocky horse trails, 5% grass, 5% pavement. I believe this is the perfect testing grounds for the Treks.

Top Two things I noticed:

  • 1:00 min to 1:30 mins faster per mile at the same heart rate in the Treks vs the KSO’s
  • Less stone bruising in the Treks vs the KSO’s
Here is GPS data on the run

Pictures after the run:

A thirteen mile trail run and these Treks look great. And how about those injinji socks!
As expected, the KSO Trek soles shrugged off the run like it was nothing.

6 mile run without Injinji socks 9/22/09

I wanted to test out the Treks without my Injinji socks. This trail is a lollypop loop with easy hills, dirt trails, creek crossings, and one knee high stream crossing. This run is for speed at aerobic levels.

I know with my VFF Classics & KSO’s I get a hot spot just before my big toe due to the internal seam. This is no longer an issue with the Treks. I still feel more comfortable with my Injinji socks and find that the Treks are easier to put on with Injinji socks.

The Kangaroo leather does not hold water. They may feel wet to the touch but you won’t be able to squeeze water out of them.

Here is GPS data on the run.

The Treks after some serious stream crossings:

Here we see the KSO Treks after some stream crossing — they’ve been soaked, but aren’t soaking wet.
Another look at wet KSO Treks.

Concluding thoughts on the new fivefingers KSO Treks

After 5 days and 24 miles of testing my new Treks, I donated my trail runners because I know they will now collect cobwebs.

Best of luck on your run Sunday, Juergs!

For more photos of Juergs’ VFFed feet (and cool socks), see his Picasa album!