Functional High-Intensity Interval Training (FHIIT) is our signature No Barbell training method—where functional movement meets purposeful intensity.

• Traditional HIIT (High-Intensity Interval Training) focuses on alternating periods of intense effort and rest, primarily to improve cardiovascular fitness and calorie burn. Most HIIT use simple, repetitive exercises (like sprints, burpees, jump squats, or stationary bike intervals) that elevate heart rate — but not all HIIT programs emphasize functional, compound movements or strength balance.
• Across Fitness’ Functional HIIT intentionally integrates multi-joint, real-world movement patterns and load-bearing exercises (push, pull, hinge, squat, carry, rotate) — giving it a broader athletic and longevity focus.