Archive · 1 Oct 2026
Why the First Minutes of Running Feel So Difficult
Starting a run can feel hard even when you are fit.
Your muscles need energy immediately, but your heart and lungs take a little time to provide enough oxygen.
During those first minutes, your breathing may feel hard and your legs may feel heavy.
Your body is increasing your heart rate, breathing and blood flow to help your muscles.
After about 10 to 15 minutes, these systems usually work together more smoothly.
This creates a steadier rhythm that makes the run feel easier.
A warm-up or slower start can help your body adjust sooner.
Regular training also teaches your body to make this adjustment more quickly.
The first 10 to 15 minutes of a run often feel unusually difficult because the body is still adjusting to increased energy demands.
Heart rate, breathing and blood flow change rapidly, but oxygen delivery cannot respond instantaneously.
During this transition, muscles temporarily rely on stored energy before oxygen supply and demand reach a steady state.
Endurance-trained athletes can increase oxygen uptake about 40% to 60% faster than amateur athletes.
Warm-ups, slower starts, regular endurance training and experience can make the difficult opening minutes less noticeable.
- Who
- Runners of all abilities, including beginners and elite endurance athletes; the article was written by Richard Taylor of Coventry University.
- What
- The article explains why the beginning of a run can feel unusually difficult and how runners can reduce that sensation.
- When
- The difficult transition commonly lasts about 10 to 15 minutes after running begins.
- Where
- The adjustment occurs in the body's muscles and cardiorespiratory system during exercise.
- Why
- Muscles demand energy immediately, while oxygen delivery and aerobic energy production take time to increase.
- Typical transition
- Many runners report that running becomes smoother after about 10 to 15 minutes.
- Physiological process
- The adjustment is called oxygen uptake, or VO₂, kinetics.
- Transition stages
- The process involves increased blood flow and oxygen delivery, rising aerobic energy production, and eventual steady state.
- Temporary energy source
- Muscles temporarily rely on stored energy while oxygen delivery catches up with demand.
- Training difference
- Trained endurance athletes can increase oxygen uptake around 40% to 60% more rapidly than amateur athletes.
- Helpful strategy
- Easy jogging, brisk walking or gradually increasing pace can prime the aerobic system before a run.
- Additional strategies
- Starting more slowly, regular endurance training and understanding the normal discomfort can also help.