Most trees have their diameter measured at breast height, which is considered to be four and a half feet above the ground on the uphill side of the tree. Sierra redwoods however, are measured at six feet above the ground. This is because of the major increase in circumference at the lower end of the tree.
With a higher exercise intensity the lactate level in the blood reaches the anaerobic threshold (AT), or the onset of blood lactate accumulation (OBLA).ccurately measuring the lactate threshold involves taking blood samples (normally a pinprick to the finger, earlobe or thumb) during a ramp test where the exercise intensity is progressively increased.
The aerobic threshold (AeT) is sometimes defined as the exercise intensity at which anaerobic energy pathways start to operate and where blood lactate reaches a concentration of 2 mmol /litre (at rest it is around 1).