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Old 23rd January 2018, 11:27 AM
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Darwinsbulldog Darwinsbulldog is offline
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Thumbs up Wimminz can't run proper bekause genetics? [FREE]

Ok, sexual dimorphism is a REAL thing. The developmental process is complex, and while there are no sharp boundaries between males and females, sexuality and gender, what we do have are two, highly overlapping bell curves that give some folks the [wrong] impression that sex is digital: female and male only.
The reality is that many people do not conform to this stereotype. Sex can be indeterminate, such as in intersex individuals, and behavioural responses are not confined to female and male heterosexuality, but form a mosaic of identities and traits that the acronym LGBTQI describes.

Although genetics determines development, it partly stochastic process. Firstly; "the recipe" was designed by evolution, and all that implies, and second environmental influences, can [and often do] modify outcomes.

You have probably seen me gob off about sexual dimorphism in dung beetles. Not only is there "male" and "female", but two versions of male. One is the large horned type, indulging in fighting for females. The other male is smaller, gracile and hornless, and using burying skills, and stealth behaviours to find mates.

Note that behaviours and morphology tend to be in tune with each other. Sometimes B & M are genetically linked, but they don't have to be. Appropriate behaviour can be learned, or derived cognitively. [Work with what you have got to do what works]. Dung beetles have enough intellectual moxie to do this, I think, but I could be wrong.

As far as morphology goes, what decides which form the male takes is not genetically coded, but nutritionally triggered. The genetics of the male allows for both types of male to develop, and the genetics of the species [females and both male forms] allows all three versions. So when the male develops, the amount of food present [detected through the insulin signalling pathway of the embryo] determines if the male is gong to be gracile or horned. If the dung bolus is large, we get the horned version, and less food gets us the "economy" version. So in hard times, we get more gracile forms, but also the mother seems to decide to roll large and small dung balls, which may indicate she is "bet-hedging".

This sort of variation is quite common in evolution. Many organisms alter form during development depending on the amount of nutrients or quality available. If a queen be dies, workers will decide to feed an ordinary female egg with "Royal Jelly" and behold, instead of developing into a worker, she becomes a queen!

Variation in performance can be altered after development as well. So can a particular lack in nutrition in sporting women sabotage performance?

Do women "run like a girl" because they lack balls, or is it more about getting the right nutrients for the phenotype concerned? It is so easy to put down differences in phenotype or behaviour down to genetics, and not think about environment. This paper explores how nutrients can help bridge the performance gap between male and female athletes:-

DiSilvestro, R. A., et al. (2017). "Enhanced aerobic exercise performance in women by a combination of three mineral Chelates plus two conditionally essential nutrients." Journal of the International Society of Sports Nutrition 14(1): 42.
Quote:
Certain essential and conditionally essential nutrients (CENs) perform functions involved in aerobic exercise performance. However, increased intake of such nutrient combinations has not actually been shown to improve such performance.
Background
Certain essential and conditionally essential nutrients (CENs) perform functions involved in aerobic exercise performance. However, increased intake of such nutrient combinations has not actually been shown to improve such performance.
Methods
For 1 mo, aerobically fit, young adult women took either a combination of 3 mineral glycinate complexes (daily dose: 36 mg iron, 15 mg zinc, and 2 mg copper) + 2 CENs (daily dose: 2 g carnitine and 400 mg phosphatidylserine), or the same combination with generic mineral complexes, or placebo (n = 14/group). In Trial 1, before and after 1 mo, subjects were tested for 3 mile run time (primary outcome), followed by distance covered in 25 min on a stationary bike (secondary outcome), followed by a 90 s step test (secondary outcome). To test reproducibility of the run results, and to examine a lower dose of carnitine, a second trial was done. New subjects took either mineral glycinates + CENs (1 g carnitine) or placebo (n = 17/group); subjects were tested for pre- and post-treatment 3 mile run time (primary outcome).
Results
In Trial 1, the mineral glycinates + CENs decreased 3 mile run time (25.6  2.4 vs 26.5  2.3 min, p < 0.05, paired t-test) increased stationary bike distance after 25 min (6.5  0.6 vs 6.0  0.8 miles, p < 0.05, paired t-test), and increased steps in the step test (43.8  4.8 vs 40.3  6.4 steps, p < 0.05, paired t-test). The placebo significantly affected only the biking distance, but it was less than for the glycinates-CENs treatment (0.2  0.4. vs 0.5  0.1 miles, p < 0.05, ANOVA + Tukey). The generic minerals + CENs only significantly affected the step test (44.1  5.2 vs 41.0  5.9 steps, p < 0.05, paired t-test) In Trial 2, 3 mile run time was decreased for the mineral glycinates + CENs (23.9  3.1 vs 24.7  2.5, p < 0.005, paired t-test), but not by the placebo. All changes for Test Formula II or III were high compared to placebo (1.9 to 4.9, Cohen’s D), and high for Test Formula II vs I for running and biking (3.2 & 3.5, Cohen’s D).
Conclusion
In summary, a combination of certain mineral complexes plus two CENs improved aerobic exercise performance in fit young adult women.
http://dx.doi.org/10.1186/s12970-017-0199-2

https://www.sciencedaily.com/release...0118175311.htm

Fig. 3:- Increase in steps after each of three treatments.
Test Formula I contained generic minerals. Test Formula II contained glycinate minerals. Step changes are mean increases in steps SD. The 95% confidence intervals for placebo, Test Formula 1, and Test Formula II were 0.5, 0.8, and 0.5 respectively. *p < 0.05 versus placebo, but not versus each other (ANOVA + Tukey multiple comparisons)
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File Type: gif 12970_2017_199_Fig3_HTML.gif (7.1 KB, 11 views)
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Last edited by Darwinsbulldog; 23rd January 2018 at 11:34 AM.
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Old 24th January 2018, 02:00 AM
Wrenn Wrenn is offline
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Default Re: Wimminz can't run proper bekause genetics? [FREE]

Would those chemical combinations have a similar effect on men or do they do something different to woman?
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Old 24th January 2018, 02:32 AM
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Default Re: Wimminz can't run proper bekause genetics? [FREE]

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Wrenn said View Post
Would those chemical combinations have a similar effect on men or do they do something different to woman?
Several things may be going on.
1. Women athletes may consume less meat than male atheists.
2. Women and men may differ in the absorption rates rates for some micro-nutrients.
3. The sexes may differ in how these micro-nutrients are utilised by the tissues.
4. A confound is that sex is not digital, but a mosaic of traits, where variance from the "norm" as it were, allows for individual differences within and between sexes. Most women run a little hotter [about a half a degree]. Exercise can induce a hiatus in the menstrual cycle, changes to vascular flows, hormonal perturbations due to exercise. Some or all of theses things could have an effect.

Last but not least I don't know for sure. Most enzymes have an operating temperature range, and a "sweet spot" temperature where they work most efficiently.

But if this observed effect is real and not an artefact of something the researchers didn't control for they may be differences in the way men and women's bodies handle micro-nutrients.
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Old 24th January 2018, 03:39 AM
Wrenn Wrenn is offline
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Default Re: Wimminz can't run proper bekause genetics? [FREE]

I was curious because I do a bit of long distance running and follow ultra marathon runners a bit. A trend that occurs is that at the marathon level (42km) woman are generally 20 minutes slower than men. But at the ultra marathon level (100km+) the gap drops a lot and woman win a share of the races.

Some reasons seem to be smaller size and better psychological ability.
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Old 24th January 2018, 09:40 AM
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Darwinsbulldog Darwinsbulldog is offline
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Default Re: Wimminz can't run proper bekause genetics? [FREE]

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Wrenn said View Post
I was curious because I do a bit of long distance running and follow ultra marathon runners a bit. A trend that occurs is that at the marathon level (42km) woman are generally 20 minutes slower than men. But at the ultra marathon level (100km+) the gap drops a lot and woman win a share of the races.

Some reasons seem to be smaller size and better psychological ability.
Interesting! I don't know how. We do know that women live longer and have fewer medical problems than men. An analogy from cars perhaps. An engine that revs really fast will wear out more quickly than an engine that is used as much, but over a longer period at slower revs.

Biological engines have regeneration capacity, but regeneration comes at a cost. The more things have to be repaired, the more cells have to be copied, proteins copied etc. So telomeres wear out, and then you start to get errors, including poor performance, and malfunctions like cancer. Unlike men, women have two copies of every gene, so there is some built in redundancy that men don't have access to. Some genes on the X chromosome don't seem to have much to do with sex.

At puberty in both sexes, cell maintenance is down-regulated, as in nature the energy budget and nutrients is re-prioritised into preparing the body for adult morphology and function. Stuff like telemere regeneration does not resume its former glory or efficiency. So basically, life after puberty is a bit like the long kiss goodbye towards death. Indeed, many species will die shortly after reproduction. [Semelparity meaning one reproductive effort, or iteroparity meaning several reproductive events before death].

There also seems to be some inclusive fitness benefit [often called the grandmother effect] midwifery skills and for post reproductive nurturing, probably because of the fact that human infants are born helpless. The prolonged childhood is probably due to our relatively large brains, and so it is no surprise that sexual traits are linked to some aspects of brain development on the X chromosome. This is because male and female "interests" can be divergent, so some male transcription factors try to make baby's head grow large, but maternal influences push in the other direction due to the constraints imposed by a large head having to squeeze through the pelvis.

Immune system. Men really are more vulnerable to disease than women [men are not being wimps when they come down with the flu, they really are sicker] . It makes sense when you think about it. When pregnant, the woman's immune system is working to protect two bodies, but she has to lower her "firewall" to let the "parasitic" exist in her body. So she becomes sensitive to stuff that will not harm her, but may harm the growing baby, ergo "morning sickness".

None of this proves why women are better than men at endurance, but not so good at "the sprint", but it seems to make sense. In nature, animals evolve an energy budget, because food is often unreliable. Reproductive function in kangaroos during droughts is a clear example of how these animals can manage their energy budgets in hard times.

https://panique.com.au/trishansoz/an...roduction.html

It is also known that pregnant women in famine situations, will pour what nutrients into the baby even at the cost of their own health and survival. So a whole lot of stuff can affect metabolism and energy use in women.

And all that is just scratching the surface regarding some of the complexities!
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Last edited by Darwinsbulldog; 24th January 2018 at 09:46 AM.
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