One would have to determine the level of muscular and cardiac work required in the hamster to run that distance (same speed and duration) to be able to correlate it with the corresponding level of exercise in the human. In rats, a running speed of 28.5 m/min has been reported to correspond to 82% of the maximal aerobic power. The methodology used for rats was very different from ours, particularly since in the study of Shepherd and Gollinick running was not voluntary. Running at a speed of 28.5 m/min, which is very close to that measured in our study for 230-day-old hamsters, would most certainly require in hamsters a much lower percentage of maximal aerobic power since they were able to sustain this average speed for hours. Also, in rats the speed was maintained at the same level for at least 10 mins, when oxygen uptake was measured. In our study, 5 min recordings of wheel turns showed that the distance/5 mins was quite variable during a running episode, which seems to indicate that hamsters were running at a much higher speed than average for some time, followed by a period of running with many short breaks of less than 5 mins’ duration. That is, speeds as high as 42 m/min have been observed on many consecutive 5 min samples followed by variable 5 min running samples of 8 to 20 m/min (data not shown). Nevertheless, since running was voluntary and decreased only in later stages of the disease, we hypothesize that the level or the intensity of the exercise was moderate and represents normal activity for hamsters in nature.
Although increased body weight due to subcutaneous edema is also indicative of the severity of disease, it appeared to be much less sensitive than voluntary running as a measure of severity because it only increased during the last three to four weeks before death and was quite variable among animals. It would also be of little value for determining sudden death but could be useful for establishing progressive failure. Best quality treatment is now available at the best pharmacy you could ever dream of: purchase antibiotics online and be sure this is indeed the best decision you could ever made for your condition to get better.