THE CONVERSATION: Why the start of your run feels so difficult
Many runners describe the first 10 to 15 minutes of a run as the hardest of all. Breathing can feel laboured, the legs can feel heavy and a pace that would normally seem manageable may suddenly feel surprisingly difficult. Here’s why this is so common and advice for easing the struggle.
The initial stages of a run are often perceived as particularly challenging by runners. Difficulty in breathing, heavy legs, and a perceived higher effort level than usual are common complaints. At first glance, one might assume these sensations are due to a lack of fitness. However, they are actually a normal part of human physiology experienced by everyone from novice runners to elite athletes.
The explanation lies in the physiological argument that begins between the muscles and the cardiorespiratory system right when you start running. While there is no way to stop this conflict, there are methods to hasten the body's resolution of it.
As soon as you begin running, your working muscles demand a quick energy supply, but the energy production system that relies on oxygen cannot respond as swiftly. In response, your heart rate increases, breathing becomes deeper and faster, and blood flow is redirected towards the working muscles. These changes facilitate greater oxygen transportation from the lungs to the muscles for aerobic energy production.
The body's adjustment process to this transition is termed oxygen uptake (VO₂) kinetics, referring to the speed at which the body can increase oxygen consumption when exercising.
This process unfolds in three stages. The initial phase concentrates on enhancing blood flow and oxygen supply. The second phase involves the muscles initiating aerobic energy production. By the third phase, oxygen supply and demand become largely balanced, reaching a physiological "steady state". Until this steady state is achieved, the body relies temporarily on the stored energy within the muscles, leading to the typical experiences of many runners.
After approximately 10 to 15 minutes, most runners notice a shift. The pace feels more manageable, breathing becomes controlled, and the run begins to settle into a rhythm. At this point, the body has largely resolved its internal conflict. Oxygen delivery increases, aerobic energy production contributes more fully, and the cardiovascular system becomes better matched to the workload. Raising muscle temperature also enhances muscle function and movement efficiency.
Although the transition period cannot be wholly avoided, there are strategies to make it less noticeable. Gradual warm-up exercises such as easy jogging, brisk walking or progressive increases in pace can accelerate the adjustment process, a concept known as "priming". Starting slightly slower than your intended pace can also help if warming up isn't feasible.
Regular endurance training, including a mix of easy runs, tempo runs, and interval sessions, can also improve the body's oxygen delivery and usage, allowing quicker adaptation when exercise begins.
Psychologically, experienced runners often recognize that the beginning minutes of a run may feel uncomfortable but don’t perceive this as a sign of a bad run. Instead, they trust the process and give their body the time it needs to settle into its rhythm. The crucial takeaway is that the sensations felt at the start of a run are typically not a sign of something wrong but evidence of the body adjusting to exercise demands before settling into a more sustainable rhythm.
Written by urgent.news from Daily Maverick's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
