Rucking and Heart Rate: Should You Stay in Zone 1 or Zone 2?
One of the biggest questions I had when I started rucking is about heart rate zones. Specifically, "When I'm rucking, should I aim for Zone 1 or Zone 2?" This is a great question—and one that could make a difference in how you approach your ruck and your overall fitness. Let’s break this down and try to find an answer.
First, What’s the Deal with Heart Rate Zones?
If you’re not familiar with heart rate zones, here’s a quick primer: these zones are based on percentages of your maximum heart rate (MHR). Zone 1 is about 50-60% of your MHR, while Zone 2 is 60-70% (but this also depends on how trained you are). Both zones focus on endurance and fat burning, but Zone 2 is often considered the "sweet spot" for building aerobic capacity. It’s also the zone where you are still able to talk with other people in complete sentences (or to yourself when you’re working out alone).
When rucking, most of us naturally fall into Zone 2, which is where you get the benefits of moderate-intensity cardio. But here’s where things get interesting: Zone 1 might be just as valuable—if not more—for certain aspects of rucking and long-term fitness.
The Science: Why Zone 2 Gets All the Hype
Zone 2 is often touted as the gold standard for endurance training. The benefits of exercising in this zone include:
Improved fat metabolism: Your body learns to rely more on fat for fuel, which is key for long-term endurance (something critical for those longer, heavier rucks).
Enhanced mitochondrial function: Zone 2 training boosts the number and efficiency of your mitochondria, which is crucial for sustained energy.
Increased aerobic capacity: This is the foundation for overall cardiovascular health and endurance.
Studies show that Zone 2 training improves markers of heart health, lowers insulin resistance, and supports metabolic function. In other words, your body becomes more efficient at doing more with less, and you can keep going longer without fatigue.
Zone 1: The Hidden Gem
Now, here’s where Zone 1 comes in. Zone 1 is often experienced as an easy or recovery workout effort - but nonetheless still an effort, so not just your regular stroll through the pedestrian area. While it doesn’t get the same love as Zone 2, training in Zone 1 has some hidden benefits—especially for people who ruck consistently.
Recovery: Moving at a lower intensity (Zone 1) can be a perfect active recovery tool. It helps flush out lactic acid and reduce muscle soreness, without adding extra strain. This can be a game changer if you’re rucking multiple days a week.
Builds a Base: Many endurance athletes, from marathoners to ultra-endurance freaks, spend a surprising amount of time in Zone 1. However, they are varying easy and hard days. If you're in this for the long haul, Zone 1 work will improve your endurance over time.
Mental Reset: Zone 1 rucking can also be an opportunity for mindfulness. You're out there, moving, but not killing yourself. It’s about resetting both physically and mentally. You’re still burning calories, but you’re also giving your brain a break, which can have massive long-term benefits for consistency and enjoyment. See also my previous newsletter on meditative rucking.
The Bottom Line: Zone 1 and Zone 2
If you’re rucking to improve overall fitness, longevity, and endurance, you need both zones in your toolkit. Zone 2 is ideal for maximizing your aerobic capacity, fat-burning efficiency, and endurance over time. But don’t ignore your Zone 1—it can be key to recovery, building a strong base, and keeping your mind in the game for the long haul.
My advice? Mix them up. Spend some rucks intentionally in Zone 2 to push your endurance, but don’t hesitate to dial back into Zone 1 when you need active recovery or just want to enjoy the journey.
It’s not just about the speed of the ruck—it’s about playing the long game.
See you out there!
BK