The Countdown Has Started
On April 26, 2026, the TCS London Marathon 2026 will bring around 50,000 runners from the Greenwich and Blackheath start to the iconic finish on The Mall. It's one of the five World Marathon Majors, and its reputation holds partly because of the course itself: certified flat, with just 119-138 meters of total elevation over 42.195km, it sets up perfectly for strong finishing times.
If you're running London this year, you're 12 days from the start line. What you do (and don't do) in these final days can meaningfully affect your race. Here's what actually matters.
Fueling: The Most Impactful and Most Missed Variable
Running experts are consistent on this point: if you've never eaten or drunk anything during your long runs, learning to fuel properly on race day is the single biggest improvement you can make to your performance. Not your shoes. Not your pace strategy. Fueling.
Your body stores roughly 90 minutes of available glycogen at race pace. Beyond that, without external fuel, you're risking the dreaded wall. For a 4-hour marathon, that means you need to be taking in fuel from around the 30-40 minute mark, not just when you start to feel tired.
The practical rule: 30-60 grams of carbohydrates per hour of running, from gels, isotonic drinks, or appropriate bars. The essential thing is don't try anything new on race day. Test your products on your last long runs to confirm your stomach tolerates them.
Shoes: Don't Change Anything Now
Your race day shoes should already be chosen, ideally broken in with multiple runs. Changing shoe models in the two weeks before a marathon is one of the most common mistakes among amateur runners. Blisters and unusual pains can turn a great race into a suffering march.
If you haven't settled on your race shoes yet and plan to buy new ones, visit a specialist running shop that offers treadmill gait analysis. This service, often free in specialist stores, identifies your pronation type and recommends a model suited to your natural stride.
Taper Week: Don't Wreck It Now
The taper is the period of reduced training volume in the 7-14 days before your race. It's often the most psychologically difficult phase for runners: you feel slow, you think you're losing fitness, you feel anxious.
That's normal, and it's a good sign. Your body is absorbing the work from previous weeks. Cut your training volume by 40-60%, keep a few short runs and brief accelerations to stay in rhythm, and sleep as much as possible.
Sleep is probably the most undervalued factor in marathon preparation. Aim for at least 7 hours a night, ideally 9, in the week before race day. Your central nervous system needs that recovery to be fully operational when the gun goes off.
Your Race Plan: The Discipline That Wins
Going out too fast is the number one mistake among amateur marathon runners. Start line adrenaline, the atmosphere, the cheering crowds: everything pushes you to run faster than planned. And often, the last two or three kilometers pay for it dearly.
The strategy that works best for most marathon runners: run the first half at or slightly below your target pace, then gradually accelerate through the second half if you've still got legs. A well-run marathon is a negative split, with the second half faster than the first.
Know your per-kilometer pace, write down your target splits, and stick to them in the early kilometers no matter what. Your race will be decided between kilometers 32 and 40. What you save in the first half, you can spend there.