What actually makes you a faster marathoner

Intensity

• Polarized vs pyramidal training: which is better?

  Two recent meta-analyses compared 80/20 polarized training with pyramidal training. Here is what they found, and what it means for your plan.

  Grade A
• How much of your running should be easy?

  Training logs from more than 119,000 marathoners and from the world's best runners point the same way. Here is how much easy running the evidence supports, and how to count it.

  Grade B
• Is Zone 2 training overrated?

  Zone 2 has been sold as a uniquely powerful way to build mitochondria and burn fat. A 2025 review found no evidence that it beats harder running. Here is what holds up.

  Grade B
• The Norwegian method and double threshold: what is actually proven

  Double threshold days and the Norwegian method are the hottest trend in running books. Here is what the research shows, and how much of it is elite practice rather than tested fact.

  Grade C
• How to set your heart-rate zones (and why 220 − age is wrong)

  Most heart-rate zones start from a formula that can be off by more than 10 beats. Here is a better order of methods, from a lab test to the talk test.

  Grade B
• Which VO2max intervals actually work?

  Four-minute reps at a hard but controlled pace have the best evidence for raising VO2max. Here is what the trials show, which session formats to use, and why heart rate misleads you on short reps.

  Grade B
• Does HRV-guided training work?

  Adjusting hard sessions to your morning heart-rate variability gives small but real benefits in trials. Here is what the evidence shows, which devices measure HRV well, and how the best trial did it.

  Grade B
• How accurate is your running watch?

  Chest straps, wrist sensors, GPS, VO2max estimates and threshold paces vary a lot in accuracy. Here is what validation studies found and which numbers to trust.

  Grade B

Load & injury

• The long-run rule that actually prevents injuries

  A study of more than 5,000 runners found that one sudden long run, not weekly mileage, was linked to overuse injuries. Here is the rule and how to use it.

  Grade B
• Does the 10% rule work?

  The rule that weekly mileage should never rise by more than 10% is running folklore. A randomized trial and a 5,205-runner cohort say it doesn't prevent injuries.

  Grade B
• How to taper for a marathon

  Cut your volume by about half, keep some faster running, and step down steadily over two to three weeks. Here is what the taper research shows.

  Grade A
• Does strength training help runners?

  Heavy lifting and jump training make running more economical. The popular claim that strength work prevents running injuries has not held up in trials.

  Grade A
• How long should your long runs be?

  Longer long runs go with faster marathons, and runners who regularly go past 90 minutes fade less. But no trial has tested the popular caps of 16 or 22 miles.

  Grade C
• Should you run at 180 steps per minute?

  There is no universal ideal cadence. A modest step-rate increase does lower knee and hip load, which can help some runners, but 180 for everyone is not supported.

  Grade B
• How should you recover after a marathon?

  Complete rest for a week is not needed. Easy running or the elliptical from 48 hours after a marathon did not slow muscle recovery in a trial.

  Grade B

Beginners, masters & women

• Is run-walk a good way to run a marathon?

  In a randomized trial, run-walk marathoners finished in similar times to continuous runners and felt much less exhausted and sore. Here is what that means for first-timers.

  Grade B
• Training as a masters runner: what changes after 40 or 50?

  Masters runners can mostly train like younger runners. Hard intervals still raise fitness at every age. What changes is a few heart-health guardrails and a little more room for recovery.

  Grade C
• Should you train around your menstrual cycle?

  Across 78 studies, any effect of cycle phase on performance was trivial. Tracking your own symptoms makes sense; a fixed phase-based plan does not. Energy and iron deserve more attention.

  Grade A

Fuel & race day

• How many carbs per hour in a marathon?

  A planned fuelling strategy of about 60 g carbohydrate an hour made recreational marathoners around 11 minutes faster. Most runners eat about half that.

  Grade B
• Why runners hit the wall, and how to avoid it

  In 4.1 million marathon results, hitting the wall cost about half an hour. It is mostly a pacing problem, and men chasing a personal best are most at risk.

  Grade B
• How much should you drink during a marathon?

  For most recreational marathoners the bigger danger is drinking too much, not too little. Here is what the research says about drinking to thirst, sodium and sweat rate.

  Grade B
• Do super shoes work for slower runners?

  Carbon-plated racing shoes reliably lower the energy cost of running, but the famous 4% comes from fast runners. At recreational paces the average gain is closer to 1%, and some runners get no benefit at all.

  Grade A
• Does caffeine make you faster?

  Across 46 randomized trials, caffeine made endurance time trials about 2% faster. Here is how much to take, when, and why you should test it in training first.

  Grade A
• How to carb-load for a marathon

  Eating more than about 8 g of carbohydrate per kilo for 36–48 hours fills your muscles' fuel stores. Most athletes don't eat enough to get there. Here is how to do it.

  Mixed
• Is keto or 'fat adaptation' good for endurance?

  Keto diets teach the body to burn more fat, but in elite trials they made athletes less economical at race pace and slower. Carbohydrate-restricted training doesn't help performance either.

  Grade A
• Can you trust marathon time predictors?

  Race-time calculators and watch predictions tend to be too fast. Here is how far off the common methods are, and how to turn them into a realistic goal range.

  Grade B
• How much does heat slow you down in a marathon?

  In elite marathoners, each degree of heat stress above about 15 °C costs 0.3–0.4% of finish time. Here is how to adjust your pace, prepare with heat acclimation, and fuel and drink safely on a hot day.

  Grade C

Myth check

• Marathon myths, checked

  Twenty-two popular marathon claims, from 80/20 training and Zone 2 to super shoes, keto and cycle-syncing, checked against the research. Each verdict links to the evidence.

  Mixed

How we grade evidence

Every verdict carries a grade for the evidence behind its main claim, not for how confident anyone sounds.

• Grade A Strong: meta-analyses or several consistent trials
• Grade B Good: one solid trial or a large, consistent cohort
• Grade C Limited: small, indirect or elite-practice evidence
• Grade D Convention: expert opinion, not tested

Specific numbers in advice, such as exact percentages or paces, are often coaching convention even when the general direction is well supported. We say so where that applies. We link to every study we cite, so you can check us. More about how we grade.