How to train for your first marathon: the complete guide

How to map out training for your first marathon

Preparing for your first 42.195 km (26.2 mile) race is fundamentally about consistency and aerobic capacity. The goal for a first-timer is not blistering speedwork; it is teaching your body to burn fat efficiently, tolerate hours on your feet, and manage in-race nutrition.

A typical first marathon training block lasts 16 to 20 weeks. Before starting week 1, you should ideally have a consistent base of running 25–35 km (15–22 miles) per week for at least 6–8 weeks.

Building the long run safely

Your long run should start around 14–16 km and progress gradually up to 30–32 km (18–20 miles) about three to four weeks before race day. There is rarely a need for a first-time marathoner to run the full 42 km in training; the risk of injury and fatigue far outweighs the physiological benefit.

Practice your race-day fueling (energy gels, hydration, electrolytes) during every long run over 90 minutes so your stomach is trained well before the starting gun.

How a 3-week taper delivers peak performance

Three weeks out from race day, you begin the taper. You will reduce total weekly mileage by ~20% in week 14, ~40% in week 15, and ~60% in race week, while keeping short bursts of marathon-pace running to maintain neuromuscular sharpness. You will arrive at the start line feeling energized and fully recovered.