Ne prva ne druga področja vadbe največkrat ne držijo. Še najmanj pa MSU, ki se ga izračuna po roznoraznih formulah. Pri meni na primer najbolj optimistična formula zgreži za 18 utripov, večina formul za več kot 20 utripov.
Za tiste, ki resneje trenirajo se področja računajo na osnovi utripa, hitrosti ali moči, ki jo dosegamo na meji LT , ker je to izhodiščna osnova, ki je dober pokazatelj naše trenutne pripravljenosti.
Višina utripa je vglavnem podedovana vrednost, ki nima nobene povezave s trenutno pripravljenostjo zato je slabo izhodišče za natančen izračun področij vadbe.
Netrenirana oseba ima svoj LT lahko zelo nizko, okoli 75%MSU, trenirana oseba pa okoli 90%MSU .
Za netrenirano osebo je področje od 80%MSU že
anaerobno za trenirano osebo pa komot
aerobno območje

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Če pa rečemo, da treniramo na 80% ali 105% svojega LT, oba trenirata pri enaki obremenitvi, čeprav trenirata pri različnih utripih/hitrosti/moči.
Lactate ThresholdAll runners and coaches talk about lactate threshold. Recall that during low intensity exercise your body is supplying enough oxygen to your muscles to easily clear the pyruvic acid and lactate produced. When you increase your speed to a moderate or hard pace, your energy demands increase. Glycolysis starts to heat up and produce a lot of pyruvate. The pyruvate starts to pile up and as a result more and more lactate is produced. Eventually you reach a speed where your production and usage of lactate is in balance. You are producing a lot of lactate, but are using an equal amount to produce energy. This is considered your lactate threshold (LT). If you were to increase your speed above LT, lactate acid would start to be produced at a faster pace than you can clear it. The accumulation of lactate causes a release of hydrogen ions into your blood. It is the accumulation of these hydrogen ions that causes the acidity in your muscle cells to rise. This is thought to be one of the causes of fatigue when running at paces above your LT. There is even some debate about whether the rise in acidity directly causes fatigue. Some of today's exercise scientists think that the acidity acts indirectly through your central nervous system to cause fatigue rather than being a direct cause.
There is a very consistent correlation between your LT and running speed. Research has shown that this relationship between LT and pace remains consistent no matter what the level of fitness. Lactate threshold levels are generally about 2.5% below current 10K pace. For most runners, that is around 10 to 15 seconds per mile slower than 10K pace. 5K pace is around 5% faster than LT, which equate to about 20 to 30 seconds per mile slower than 5K pace. Most runners reach LT at around 10 mile race pace.
Vir: RunningPlanet.com
Prav iz tega razloga skoraj vsi tekaški trenerji podajajo zone obremenitve v obliki potrebnega tempa in ne potrebnih utripov

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