Aspire Fitness Test

The aim of the experiment was to compare two different sets of crank shafts, with the 1st test using regular cranks 170mm long (“Regular 170 Cranks”) and the 2nd test using experimental cranks ZENcranks 184mm long Power Augmentation System with integrated ZENpedals (“ZENcranks PAS 184”).



One 52 year old cyclist completed the two tests with 5 days between each test for recovery. The protocol was a incremental test to exhaustion, starting a 180w and increasing 20w of power every 3 minutes until the subject failed to complete a stage. Several variables were measured during the protocol including blood lactate, heart rate and rate of perceived exertion. Before the test commenced ambient temperature, urine omolality, blood glucose and blood lactate were also determined. The subject was asked to repeat the same training and nutrition the day before the tests.


Figure 1



Fig 1: Graph observing heart rate during an incremental test to exhaustion with Regular 170 Cranks (Heart rate 1) and experimental set of ZENcranks PAS 184 (Heart rate 2)

Heart rate was observed to be lower through out the incremental test to exhaustion using ZENcranks PAS 184. The average difference in heart rate between test 1 and test 2 was 15.66 ± 2.3.







Figure 2



Fig 2: Graph observing Blood Lactate during an incremental test to exhaustion with Regular 170 Cranks (Lactate 1) and ZENcranks PAS 184 (Lactate 2)

Blood lactate was measured every 3 min during the incremental test. The lactate points from ZENcranks PAS 184 were considerably lower than those from Regular 170 Cranks, averaging 3 ± 1.4 mmol/l-1 lower. As the test progresses we see a incremental increase in lactate from both tests but also an incremental increase in the difference between the 2 tests as seen in table 1.





Table 1. Incremental test with Regular 170 Cranks (Lactate 1) and ZENcranks PAS 184 (Lactate 2)


Table 1
Lactate (mmol-1) 1 Lactate (mmol-1) 2 Lactate diff
180 2.9 1.1 1.8
200 3 1.4 1.6
220 3.7 1.7 2
240 5.1 2.2 2.9
260 7.4 3.1 4.3
280 9.4 4.2 5.2
300   6.7  


Conclusion and limitations

The data observed above would suggest a significant difference between the 2 sets of cranks. The heart rate and blood lactate data was considerably lower for ZENcranks PAS 184. Lactate threshold was also at a higher wattage for the ZENcranks PAS 184 test. The subject could have completed another level during the experimental test, however there was no point as we had all the data we needed.

There are several limitations to the experiment. The ambient temperature during the 1st test was 27o whereas the temperature was 23o during the 2nd test.

The subject was well hydrated during the 2nd test, whereas during the 1st test the subject was significantly dehydrated.