The reason a HRM (Heart Rate Monitor) is so crucial today for some one like Randy (and I am sure if Lydiard had access to this tool he would have undoubtedly used it) is that you don’t have a coach who can stand next to the edge of a track while you run laps and prick your finger and take blood samples to find out your lactate levels. But you can get the point at which your LT level spikes from the comfortable 2mmol level (where you can run a marathon) to 4mmol and up.
From this information Randy, you will then know at what paces you must train. Right now you are mostly going at it as a shot in the dark. It’s like the guy who thinks he wants to run a 34 min 10k saying, OK, that’s 5:30 pace, everyday I am going to just come out here and blast a 5:30 pace for as long as I can and eventually I will be able to add distance until I get to 10k. WRONG!
When you die near the end of a marathon you have borrowed too much from anerobic system to fuel your aerobic system. If you had taught your body to burn fat as a fuel vs glycogen you can run longer.
Yes, a quote from Hadd.
Let’s look at some major negative effects of “borrowing” from your anaerobic ability in a distance event (anything from 5k upwards). (For those of you who do not think you are doing this, just note that if you have a poor(er) pace relationship as the distances increase, you are.)
1. When the muscle cells in your legs build up too much acidity (caused by running anaerobically), those cells shut down since the acidity inhibits enzymatic action and contractibility in the cell and energy breakdown can no longer continue. So, the more you are trying to stoke the boilers, pour on the speed, and fire on all cylinders, the more some of those cylinders are shutting down. This is not so if you use those self-same cells/fibres aerobically.
2. Breaking a molecule of glucose down into energy anaerobically is horrendously wasteful of fuel. It will result in fuel economy the equivalent of “2 miles per gallon”. Breaking that exact same glucose molecule down into fuel aerobically results in “36 miles per gallon”. If you are going far enough (HM or marathon), you better be as economical as possible and get as many miles as possible per gallon because otherwise you are going to run out of fuel and crash long before the finish line. Note that the muscle cells that are operating anaerobically will be unable to access your huge store of fat as a fuel (which would give you wayyy better than even 36 mpg). Fuel which would ensure you get to the 20 mile mark and still find you can pour it on.
Think of it like this. Put the smallest compact car you can think of, and a Ferrari, side by side. Empty both fuel tanks, give both of them one gallon of fuel and tell them to go as far as possible. Which is gonna win?
Since your LT measures at what pace you change over from aerobic to (increasingly more) anaerobically-fueled running, it is also a measure of when you stop being economical and become more and more uneconomical. So, we can also say that a low (poor) LT also means poor fuel economy.
Many of you will be able to give examples of guys (I know at least two) who can crank out 20 mile long runs at 6.00m/m and yet not finish a marathon at that pace. Why? Because, due to their precise fuel economy (or lack thereof) they cannot store enough carbohydrate to get them through the final 6.2 miles. Their fuel economy, and therefore their LT, is too low.
I have access to more information then this Randy if you are curious. But the one thing I will re-iterate is if you are interested in LT type training as a marathoner and the science that is involved, without having direct access to someone pricking your finger, an HRM is the only thing you can use as a substitute. There is no denying this despite what others, who don’t really know, say.
But that is not to say you can’t become a great marathoner without one, you can. People have done it for years. But wouldn’t it be nicer to really know what you are doing rather than taking a stab in the dark?