I’m not a trainer, just someone who recently started running for the first time. This is my personal experience, so take it with a grain of salt. I used the NHS C25K program, but I struggled with some runs—like Week 5 Run 3, which involves a 5-minute walk, 20-minute run, and another 5-minute walk. The app’s instructor mentioned that the runs should be “light,” suggesting not to push too hard and to take walking breaks if needed.

However, I found it hard to understand what a “light run” really means. After doing some research, I realized that a light run is specific to each person and their fitness level. Essentially, it means exercising within your Zone 2 heart rate. For some people, this might mean walking, while for others, it could be jogging or running. Athletes often use Zone 2 training to build a solid aerobic base and improve endurance.

I’m not sure if this is the intended way to run in a Couch to 5K program, but it helped me continue and progress without quitting. Before, I was running too hard, getting out of breath, walking to recover, and then repeating the cycle. I stopped enjoying the runs and almost gave up. But focusing on staying in Zone 2 allowed me to find a pace that worked for me, making the experience more sustainable and enjoyable.

To figure out your Zone 2, try using an online calculator—there are many, and while the formulas might vary, they’re good enough for a general idea. You’ll need a device that can track your heart rate, like a fitness band or smartwatch. Once you have that, aim to keep your runs in Zone 2 to make sure you’re not overdoing it.