Why Hill Repeats Beat Long Flat Rucks

If you only have an hour, hill repeats build more usable rucking fitness than a flat plod ever will. Here is the workout and the reason it works.

By Rich Borgatti · Training · 2026-06-18

Most ruckers I know do the same workout every week: throw 30 lb (14 kg) on, walk for an hour or two on the flattest path they can find, and call it training. It is fine. It builds a base. But if you only have 45 to 60 minutes and you want every minute to count, you are leaving real fitness on the table by skipping the hills. Here is the case for hill repeats, and the workout I would prescribe to most ruckers reading this. Why hills hit different When you walk on flat ground with a weighted pack, the work is steady and modest. Your heart rate settles into a comfortable aerobic zone, your stride is the same one you have used a million times, and after the first 15 minutes your body has basically figured it out. The benefit is real but small per minute. That is why a flat ruck has to be long to deliver much training stress. Climb a hill with that same pack and three things change at once: Heart rate goes up. Even a modest 5 to 10 percent grade will push you out of "easy" pace and into a zone where your aerobic system actually has to adapt. That is where cardiovascular fitness comes from, not from another hour at a stroll, but from time spent at the upper end of what you can sustain. Your hamstrings, glutes, and calves do the work. Flat walking is mostly quads and hip flexors. Climbing recruits the posterior chain, the same muscles that carry you up real terrain, prevent knee pain, and protect your lower back when the pack is heavy. Your stride changes. Going uphill, you lean slightly forward, take shorter steps, and use your ankles more. This trains range of motion and…