Warrior Playground at Grit Fitness

Ninja Workout and Grit Fitness

Scott Sundahl and his son Braden, 7, try to climb an obstacle during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016

Ninja Workout and Grit Fitness

Betty Markwardt, 6, navigates an obstacle during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016

Ninja Workout and Grit Fitness

Braden Sundahl, 7, swings from a rope to another obstacle during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016

Ninja Workout and Grit Fitness

Preslee Culjat, 6, climbs an obstacle during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016

Ninja Workout and Grit Fitness

Preslee Culjat, 6, gets help from employee Mike Wilson on an obstacle during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016

Ninja Workout and Grit Fitness

Preslee Culjat, 6, left, and Betty Markwardt, 6,navigate an obstacle course during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016

Ninja Workout and Grit Fitness

Braden Sundahl tries to climb a peg wall during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016

Ninja Workout and Grit Fitness

Braden Sundahl, 7, runs across an obstacle during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016

Ninja Workout and Grit Fitness

Braden Sundahl, 7, climbs an obstacle during a children's exercise class at the Warrior Playground at Grit Fitness on Sunday in Longmont. For more photos of the workout go to www.dailycamera.com Jeremy Papasso/ Staff Photographer/ Dec. 4, 2016