Watch PhysiVāntage Pro Jonathan Siegrist Send "Flex Luther" 5.15a

Soon after snagging the second ascent of Rifle's hardest route, Kinder Cakes (5.15a) in August, PhysiVantage athlete, Jonathan Siegrist, ventured to a crag far off the grid for his next project. 

Colorado’s Fortress of Solitude is everything that Rifle isn’t: wild, secluded, and far off the beaten path. Nothing at this crag comes easy. It sits at the top of a steep 45-minute approach, with fewer than a handful of routes clocking in below 12b. The rock hasn’t seen much traffic over the years since Tommy Caldwell established many of the routes in the early 2000’s. 

Flex Luther is the hardest of the lot at the Fortress at 5.15a. It’s seen just four ascents now over the years: Caldwell himself with the FA in 2003, then a long wait until Matty Hong ticked it in 2020 followed by Carlo Traversi in 2021. 

Siegrist had first eyed the route when he sent its neighbor, Kryptonite (5.14d) back in 2010. But intimidation deterred him from Flex Luther for the time being. 

“There are always stories circulating of climbers going to try [Flex Luther] and essentially deciding against it due to its obscure location...and difficult finding partners”, Siegrist says. “It kept suitors away for a really long time.” 

After Hong and Traversi put Flex Luther back on the map, Siegrist began to see it in a different light. Their effort and excitement inspired him to find the charm beneath the choss too.

J-Star sent Flex Luther on Halloween (2022). Filmmaker Cameron Maier boils down the wild ride into a short film (below) that follows Jonathan Siegrist and Matt Segal on their adventures at the Fortress of Solitude this past Autumn.

Join us in celebrating Siegrist’s ascent of this legendary route that puts the spice back into sport climbing.

Watch the send now!

J-Star's Performance Nutrition

On climbing days, Jonathan uses Endure X to promote optimal blood flow, power-endurance, and recovery between routes and redpoint burns.

As a post-workout smoothie or with a meal, J-Star's protein supplement of choice is PhysiVāntage plant-based Powerplex.

If you'd like to feel some of the same benefits as Jonathan, you can try PhysiVāntage and save 15% on full-priced nutrition by clicking on this link.