One for the endocrinologists!

Nelson Longflap

Every year around mid September I start to suffer from depression, and self medicate with hypericum which works, but takes a few days to kick in. When I'm feeling more positive (usually no more than ten days off) I'll get back out on my bike, but find that all my speed and leg strength have gone, but my base is more or less intact. So my average will drop from around 18mph (upper level 2) to around 16.5mph on my usual 60 mile loop. Now, this doesn't happen during the summer even if I have to take off a similar amount of time. I'm guessing that there must be a drop off in hormone levels along with the amount of effective serotonin knocking about in the brain. Anybody?

sward29

Could be that it's Autumn and the wind's picking up

Nelson Longflap

Wish it was that!. I can usually fly up hills (9 1/2 stone, 5' 7''), but come autumn I can't do them either - well, not without having to resort to touring speed. I just feel as if there's a natural/physiological adaptation to the onset of winter, i.e., the body starts to slow down and stops producing its own 'performance' chemicals.

Zendog1

Muscles loose about 20% in power output going from summer to winter temperatures (extreme simplification ). This is the biochemical consequence of cooling the various chemical reactions needed for muscle contraction below optimum operating temeratures.
The endocrine system may be involved in the winter slow down but its mainly just the cold.

ut_och_cykla

No expert but any imbalance in hormones/enzymes will affect performance. All kind of things can' wobble', thyroid, cortisol production (to name the only two I can think of)
Assuming teh depression is chemically based (hormones/enzymes) it could well be that others are affected too. Moderate daily exercise is said to be a big help in dealing with mild depression.

Pagem

Zendog1 wrote:

Muscles loose about 20% in power output going from summer to winter temperatures (extreme simplification ). This is the biochemical consequence of cooling the various chemical reactions needed for muscle contraction below optimum operating temeratures.
The endocrine system may be involved in the winter slow down but its mainly just the cold.

source?

i don't believe this to be the case at all. physical performance is certainly decreased by extremes of temperature but assuming one doesn't go for long rides at 6 degress in summer kit i really don't beleive this to be the correct.

on a winter ride i would expect to be 'up to temperature' within 10-15 mins.

Pagem

Nelson Longflap wrote:

Every year around mid September I start to suffer from depression, and self medicate with hypericum which works, but takes a few days to kick in. When I'm feeling more positive (usually no more than ten days off) I'll get back out on my bike, but find that all my speed and leg strength have gone, but my base is more or less intact. So my average will drop from around 18mph (upper level 2) to around 16.5mph on my usual 60 mile loop. Now, this doesn't happen during the summer even if I have to take off a similar amount of time. I'm guessing that there must be a drop off in hormone levels along with the amount of effective serotonin knocking about in the brain. Anybody?

without looking into it i would believe in your case this is exactly the reason for your physical performance drop. serotonin reduction due to less exposure to natural sunlght would certainly give one issues with feeling tired or 'low' so motivational factors become a serious problem.

it's alwasy easier to ride well wehn you're happy - when you're off par things always seem more of a struggle.

There is an issue with testosterone and dhea ratio:

http://www.anthropogeny.com/Why%20We%20 ... Winter.htm

physcial perfomance can be affected by extremes of temeperature, not least on the simple properties of muscle fibres through to the cardiovascular and respiratory systems. however, wearing the right kit and ensuring you're "dressed for the weather" should significantly negate these issues.

ColinJ

You might like to take a look at my posts (pages 2 & 3) on this thread over on Cycle Chat.

Nelson Longflap

I have no doubt that I get a bout of SAD come September, but I've got the mental side nailed now. I Tried a light box a few years back, but it didn't have any noticeable effect on me, and I'm lucky that I don't have to work in an office, so can get out during natural daylight hours to get enough full-spectrum light - but my legs still feel markedly sluggish even when the depression has apparently gone. Interesting that Pagem's link indicates an increase in testosterone around autumn. I feel as though it's the opposite (lowered sex-drive - all of that!). Perhaps it's just something simple like the body having to adapt to breathing in colder air.

Thanks for your input chaps and keep 'em coming.

Zendog1

Pagem wrote:

Zendog1 wrote:

Muscles loose about 20% in power output going from summer to winter temperatures (extreme simplification ). This is the biochemical consequence of cooling the various chemical reactions needed for muscle contraction below optimum operating temeratures.
The endocrine system may be involved in the winter slow down but its mainly just the cold.

source?

i don't believe this to be the case at all. physical performance is certainly decreased by extremes of temperature but assuming one doesn't go for long rides at 6 degress in summer kit i really don't beleive this to be the correct.

on a winter ride i would expect to be 'up to temperature' within 10-15 mins.

The source on the muscle efficiency loss was from a level 2 Open University course on human biology. As I said it is an extreme simplification but well documented. Your core temp may well be maintained but periperals experience a level of cooling - ever get cold feet / hands ? I certainly do.

Pagem

Zendog1 wrote:

Pagem wrote:

Zendog1 wrote:

Muscles loose about 20% in power output going from summer to winter temperatures (extreme simplification ). This is the biochemical consequence of cooling the various chemical reactions needed for muscle contraction below optimum operating temeratures.
The endocrine system may be involved in the winter slow down but its mainly just the cold.

source?

i don't believe this to be the case at all. physical performance is certainly decreased by extremes of temperature but assuming one doesn't go for long rides at 6 degress in summer kit i really don't beleive this to be the correct.

on a winter ride i would expect to be 'up to temperature' within 10-15 mins.

ever get cold feet / hands ? I certainly do.

no, i dress for the weather.

even if your hands and feet are cold this isn't going to effect performance on the bike so long as the muscles that are required to drive the bike are at optimum temperature.

Pagem

Nelson Longflap wrote:

I have no doubt that I get a bout of SAD come September, but I've got the mental side nailed now. I Tried a light box a few years back, but it didn't have any noticeable effect on me, and I'm lucky that I don't have to work in an office, so can get out during natural daylight hours to get enough full-spectrum light - but my legs still feel markedly sluggish even when the depression has apparently gone. Interesting that Pagem's link indicates an increase in testosterone around autumn. I feel as though it's the opposite (lowered sex-drive - all of that!). Perhaps it's just something simple like the body having to adapt to breathing in colder air.

Thanks for your input chaps and keep 'em coming.

if we accept that perhaps testosterone increases thorugh autumn and winter than the immune system can fall in response. this, as with anything else in life, affects some people more than others. it may be possible that you're not recovering enough through the winter between rides due to this immune repsonse.

i'm quite happy to let my physical perfomrance drop over winter since i see it postively as a natural break in the racing calender and time to allow for true recovery and steady, unhurried base building.

Zendog1

This quote thing sucks - can you just quote a phrase not the whole post?

Anyway I am impressed that you can maintain optimum muscle temperature all the way to your feet irresepective of the conditions.. The OP at 9.5 st will have a temperature gradient in his legs that will reduce muscle performance when it gets cool.

Oh and could you give me a source for your "belief" that this is not the case.

Pagem

Zendog1 wrote:

This quote thing sucks - can you just quote a phrase not the whole post?

Anyway I am impressed that you can maintain optimum muscle temperature all the way to your feet irresepective of the conditions.. The OP at 9.5 st will have a temperature gradient in his legs that will reduce muscle performance when it gets cool.

Oh and could you give me a source for your "belief" that this is not the case.

hey, don't get upset. i have quite a good understanding of human physiology. from this i don't believe what you say to be totally correct. it is my opinion - hence why i said belive.

i referenced a source for the testoerone - dhea theory for a view point that i hold.

you so far have supported your ideas with nothing.

ut_och_cykla

I've read the same OU course - I took the cold muscle reference to mean that warming up is important if you want to achieve max output from muscles. I think if you dress appropriately the main muscles involved in cycling will attain a good working temeprature because they are working and generating heat.

Undoubtedly cold has an effect on performance - but this can be addressed by clothing etc. Warming up might take longer etc.

If you are unwell (mentally or otherwise) the disturbance of all the myriad of different hormone & enzyme systems will also affect performance. Furthermore if you have 'peaked' during the summer, yuo can't stay at the same level for any length of time.

I personally believe (tho' have no scientific support to hand) that winter/day length etc does have an impact on how we feel about life and therby how we perform at sports etc. Melatonin levels are affected by light exposure and in turn it affects gonadotropin inhibitory hormone and the sex hormones in men and women. Its a complex thing the body...

Hudster

Not a clue for the reason, but I go through a very similar thing. I am also very light at just under 10stone and I can really feel the cold. I also suffer with the bad light during winter - where I live is very cloudy and doesn't have very good light during the winter months.

However, my body certainly changes for the winter. During late September/ October I go through a week when I'm feeling like I'm getting a cold, but don't actually get one. From then on, I feel quite sluggish. If I monitor my resting plus, it increases quite significantly - by more than 10bpm, even if I'm warm.

I don't worry too much about it as I know when the spring comes my body will adapt back (I have the weird getting a cold feeling at this time as well). The main problem I suffer with is mentally. I really hate winter :

Nelson Longflap

Actually, It's not the cold that produces the performance drop. I remember the same thing happening last year and the year before, when the temperature stayed into the 20's until early Oct, and if anything I overdress in colder weather and strip off when warmed up. It's just annoying that my ability to perform comes to an abrupt end around mid-september (when I'm at my peak!) irrespective of the temperature, and always coincides with the onset of depression (which I successfully treat with St John's Wort). So it's probably light-related.

Philosophically speaking, there's the choice of having a bit of a mental and physical rest from cycling and returning with vigour in the new year, or training through the sluggishness with short and painful anaerobic work (which can stimulate Growth Hormone I think - precursor to other hormones?) and perhaps hitting new highs next year. In short, I just have to accept that this is what my body does - just wish I knew exactly WHY? :?

Edwin

Is it possible this could be related to the cardiovascular system? I find it much harder to breathe when the air is colder, and would have thought this affects the amount of oxygen reaching the muscles. Could be a bigger factor than muscle temperature....
There's other factors as well, for example air resistance increases in colder, denser air (probably negligible) and wearing extra clothing will increase drag as well. I've slowed down noticeably in the last few weeks, my 8.6 mile commute going from 22 minutes on a good day up to 25-26 minutes. Traffic increases after the summer period which doesn't help, so there's plenty of excuses not to worry about it!
Having said that, it *is* annoying..........

Alex_Simmons/RST

Edwin wrote:

There's other factors as well, for example air resistance increases in colder, denser air (probably negligible) and wearing extra clothing will increase drag as well.

Air temperature has a sizeable impact on air density (as does air pressure, humidity does as well but it's impact is minimal), which in turn can impact power/speed quite significantly.

For example:
A sample* rider riding at 36kph (22.4mph) on a flat road
at 30 C (86F) requires 175 watts
at 0 C (32F) requires 192 watts or 10% more power.

OR
A sample rider riding at 200W
At 30 C would travel at 37.8 kph (23.5mph)
At 0 C would travel at 36.5 kph (22.7mph) or 4% slower

* standard rider example with a CdA of 0.25 (pretty slippery for a roadie), 75kg on a flat asphalt road with air pressure constant at 1020HPa and relative humidity at 50%.

thebikeliker

I think it is because the zanadiffrin levels are reduced at the same time as the optimaxial peak is lagging behind the wheid. I compensate for this by using my period of guberment to take advantage of the abundance of porter’s tines that is about at this time. Only when the observed rate of kybrid production is equal to the actual cretabic deficit do I try and go hard.

I’m surprised that no one else has mentioned this.

Sources: Balfour’s Better Biking and McGurty’s Training Techniques for Tired Troons.