Bit more intensity tonight but not a particularly tiring session on the turbo doing 2x5 minutes @ 300W, 300W felt "Ok" tonight, not as hard as it has felt, more manageable. Took the opportunity to do a blood lactate test at the end of the 2nd 300W effort and the reading was 3.7mmol/l.
This seems to suggest that things are heading the way I want them to, I've looked back at some previous blood lactate measurements done during various sessions and this is the lowest blood level measured at 300W so far, previous data follows:
25.10.2007 3.7mmol/l @ 300W *
06.08.2007 4.4mmol/l @ 260W
26.06.2007 3.6mmol/l @ 235W
07.06.2007 5.1mmol/l @ 300W
01.06.2007 4.2mmol/l @ 300W
The above information was collected in slightly differing conditions, inevitably, but the results are quite encouraging and are heading in the right direction, seems like a good explanation for why my legs don't seem to be suffering so much! If, as is suggested by a number of people, the "lactate threshold" lies at or about 4mmol/l this suggests that my threshold power is starting to approach 300W. I want to do a FTP test soon (essentially a 20 minute TT on the turbo) to see what my FTP is and I can use this to guide my power training levels as time goes on.