Why Your Marathon Training Fails On Race Day
WHAT PROOF DO YOU HAVE THAT YOUR TRAINING IS WORKING
If your marathon training is working right now, what is your proof? Not your opinion. Not how Sunday felt. Your proof. And if it is not working, how many weeks would go by before you actually found out?
Most runners find out at 30km. The pace you trained for stops being available, there is still an hour of racing left, and there is nothing you can do about it. Sixteen weeks of work, and the first honest report you ever get is the one that ends your race.
You do not have to train that way. Ask yourself when you last ran the exact same route at the exact same effort and actually compared the two runs. If the answer is never, you have no evidence either way. Coach Joe Friel is clear on this. Your heart rate is the input, the effort going in, and your pace is the output, what that effort produced. Compare the two and the change in your fitness becomes visible. Skip that comparison and your training block is sixteen weeks of guesswork that only ever gets graded on the one day you cannot fix anything.
THE THREE MARKERS THAT LIE TO YOU
Three things go wrong, and you are probably doing all three.
You trust the feeling. You decide whether the block is working based on how the run felt. Feel moves for reasons that have nothing to do with your fitness. Sleep, heat, work stress, a heavy week, all of it changes how a run feels without changing what you can actually do. How hard your runs feel over several weeks is a poor predictor of anything.
You track one number. You go looking for something harder than feel, and you land on resting heart rate or overnight heart rate variability. One number on its own tells you how recovered you are this morning. It does not tell you whether you got faster, because it has nothing to compare itself against.
You never repeat anything. The run you would compare against does not exist. Different route, different wind, different time of day, different week, different fatigue. You ran hard on Tuesday and easy on Sunday, and neither one tells you anything, because neither has a twin. Nothing in your sixteen weeks is comparable to anything else. Even if you got dramatically fitter, there is nothing in your files that shows it.
WHAT THE RESEARCH SAYS ABOUT REPEATING THE SAME RUN
A 2016 study published in the International Journal of Sports Physiology and Performance tested whether one repeated run can track your fitness. Thirty five endurance trained men and women aged 20 to 55 were followed for 18 weeks. Every week they ran the same three stage maximal test out on the road, not in a laboratory, with full laboratory testing at week zero, week 9 and week 18.
The speed held at each submaximal stage tracked laboratory endurance performance. The change in speed at 80 and 90 percent of maximum heart rate tracked the change in peak running speed. Heart rate recovery, the number most runners reach for first, was the weakest measure in the whole study. How fast you move at a fixed submaximal heart rate, repeated weekly on the same route, tracks real fitness closely enough to stand in for a laboratory.
I coached a midpack runner through a sixteen week block who was certain he was going backwards, because every long run felt harder than the last one. His pace at the same heart rate on the same loop had improved by 11 seconds per kilometre, 18 seconds per mile, across those weeks. He was about to tear up a plan that was working. That is happening to you right now, and the only reason you cannot see it is that you have never run the same test twice.
THE SESSION THAT PROVES YOUR FITNESS EVERY 10 DAYS
Here is the session, and you can run it this week. Pick one flat route you can run again and again, roughly 8km or 5 miles, and run it at the same time of day. Warm up with 10 minutes of easy jogging. Run 40 minutes at steady aerobic effort, the effort where you can speak in full sentences, and hold that effort start to finish. Cool down with 10 minutes easy.
Afterwards, split the run in half and compare your average pace against your average heart rate for each half. A drift of 5 percent or less and your aerobic endurance is sound. More than that and you have your answer while there are still weeks left to act on it. Repeat it every 10 days. Same route, same effort, same time of day. The number moves, the session does not.
Feel is still information, but it is never the verdict. When feel and comparison disagree, the comparison wins. You will know you have this right the first time you finish a run that felt awful and the file on your watch tells you it was one of your best.
That is what this buys you. You walk to your start line already knowing you are fitter. You stop tearing up plans that were working, because one heavy week stops looking like failure. And you catch the block that genuinely is not working in week six, when you still have 10 weeks left to change it. Stop asking your legs how the block is going and start asking the files on your watch. If you want your training block built and checked properly from the first week, personalised coaching with Run The Race does exactly that.