How many sexes?

Is TE the only relay/ultra site that covers both Bayesian inference and complex human biology? Or is it merely drugs and sex?

It’s hard to write about biological sex. Our language about sex is overloaded, and our bias toward wanting the world to be as simple as it sometimes appears interferes with seeing things as they are.

With some sensitivity ‘disorders of sexual development’ (DSD) is the preferred medical umbrella phrase for women who do not have two X chromosomes or have markedly different development. It is often presented as ‘differences of sexual development,’ an obscuring phase: every woman alive can recall different rates of development between herself and her friends during puberty and think, of course there are differences in sexual development. But that is not what the phrase represents. ‘Intersex’ is also used, preferred by many intersex people. An inclusive phrase: it ranges from gender dysphoria all the way to women with a Y chromosome and internal testes.

We think of two sexes, but there are eleven chromosomal sexes, even counting XY as only one. (It’s not.) There are X (Turner syndrome), XX, XY, XXX, XXY (Klinefelter), XYY, rarely XXXX, XXXY, XXYY, and extremely rarely XXXXY and XXXXX. We mistake the ‘XX-or-XY’ majority for the totality.

Testosterone is our chief sex-determining hormone. Testosterone is highly ‘conserved,’ meaning it’s so useful that it’s been around in the same form for hundreds of millions of years. It’s produced by bacteria, plants, fish, insects, trees. Testosterone and some of its derivatives (called androgens) are necessary for male sexual development, but estrogen is also derived (via aromatase) from testosterone. Lipophiles: they’re made from cholesterol, which is a fat.

In humans testosterone follows a disjoint (non-overlapping) bimodal distribution. Height is a bimodal distribution, but it is conjoint (overlapping). Most men are taller than most women, but plenty of women are taller than plenty of men. Testosterone is not like that. The highest XX women have testosterone levels four-or five-fold lower than the lowest XY males.

If height was like testosterone, the shortest healthy adult male would be taller—by a lot—than the tallest healthy adult (XX) female. During puberty boys’ testosterone levels are 20 to 30 times higher than girls.

There are some DSDs that elevate XX women’s testosterone. Polycystic ovarian syndrome (PCOS) is an example, and it is not a surprise that, according to what we know so far, the subset of PCOS women who also have elevated (for women) levels of androstenedione are represented in elite sport at roughly three times their presence in the general population. (Note that PCOS women still have testosterone levels within the XX band.) This is not so for XX girls/women with congenital adrenal hyperplasia (CAH), a DSD also characterized by high testosterone levels. (Boys can also be born with CAH but unlike with girls it has no measurable behavioral effects.) CAH can have health consequences for girls. CAH girls show boy-leaning play preferences, even with rigid gender-ideological parents, and are much more likely than their non-CAH sisters to choose ‘thing-centric’ professions, like carpentry or engineering. (They on average make more money than their sisters, too.) The evidence is not extensive but even non-CAH XX girls exposed to higher levels of in-utero testosterone show a greater preference for ‘boy’ play. (Play, like height, is bimodal but overlapping; CAH and high in-utero testosterone girls play like girls, simply mixing in a slightly greater dash of boyish activities. Roughhousing is an example.)

There is a subset of DSD girls and women who have Y chromosomes, and whose bodies correspondingly produce sperm rather than eggs. There is a range of somatic expressions: complete androgen insensitivity syndrome (CAIS) and PAIS (partial), to 5-alpha reductase deficiency (5-ARD). CAIS women lack ovaries and a uterus but otherwise are physically and behaviorally women, indistinguishable from their XX sisters. They have internal testes, but the ‘default’ body for humans is female, and CAIS women, who produce testosterone and other androgens but do not have receptors for them—their bodies ignore them—grow up and live as girls and women.

5-ARD is different. These women also have internal testes producing male levels of testosterone. Unlike CAIS or PAIS, they have functional androgen receptors (which are coded on the X), but a deficiency in 5-alpha reductase, an enzyme needed to convert testosterone to dihydrotestosterone (DHT), which is a more potent androgen variation that during puberty causes male secondary sexual characteristics to develop. 5-ARD levels vary: some 5-ARD childhood girls have enough of the enzyme that at puberty they express/become boys, e.g., what seemed to be a clitoris develops as a penis, testicles descend outside the core, &c. Some don’t, and live their lives as women.

Identity and biological status don’t always track. For instance CAIS women don’t commonly discover their chromosomal status until their friends start menstruating at puberty and they don’t. (Parents and other adults can … not behave well when they learn their little tomboy has a Y chromosome. Lucky is the child with emotionally generous parents.) The increase in trans people (gender dysphoria) has been correlated with hormone-disruptors (microplastics, other synthetic chemicals) in the air and water, but research is in early stages, and is both time-consuming and combinatorially difficult.

XY individuals have roughly 12% higher hemoglobin levels. Hemoglobin carries oxygen; oxygen metabolism is generally regarded as the limiting factor in any kind of high-output endurance athletics. As a runner, you may be able to sprint at the same pace that Eliud Kipchoge or Brigid Kosgei run marathons but you quickly hit oxygen debt, while neither he nor she are even close.

Does higher testosterone (with functional androgen receptors) result in superior athletic performance? No and also yes. Not generally for men within the normal male range, where there’s a ‘sufficiency’ model, viz., unneeded testosterone is biologically ignored. For women, unequivocally yes, when it ranges outside the healthy-XX-female band.

Evidence: the standing women’s world records and top-ten lists in track and field. Women who are nudged (or forced, as was the case with Russian, Eastern European, and Chinese athletes with state-sponsored doping) in the direction of male levels of bone density, muscle composition, and oxygen-carrying capacity are stronger and faster than women of similar or even greater talent who are not synthetically jacked.

The analogy with Michael Phelps is frequently raised: Caster Semenya, the most well-known 5-ARD XY woman, as the female equivalent of Phelps. This is a false analogy. Phelps was (is) at the edge of the male distribution in physical capacity, which is entirely unsurprising in an elite athlete. He is still within the male range. There are many NBA players with longer arms and bigger feet. There are no XX women, truly not one in the world, with testosterone levels as high as Semenya. Phelps is an extreme male, but Semenya is not an extreme XX female.

This does not mean Semenya and others with 5-ARD XY are not women. It does mean that simple dichotomous thinking, that there are exactly two sexes, is in error.

For sport, it means that XX women, no matter their talent, competitiveness, and the intelligence of their training, cannot win against moderately talented XY women. Inclusiveness is good, but not without examination. In the case of sport, inclusion of 5-ARD XY women disadvantages all XX women.

In careful academic writing a distinction is made between sex, a biological condition, and gender, an interpersonal and social status. Sport is appropriately segregated by biological sex, not by gender. For fairness, women’s sports should include XX women only.

For TE everyone (vaccinated) is welcome of course. No-one has to spit into a cup.

Your perfect running form

I can’t tell you your perfect running form, as it cannot be fit into words.

We use ‘form’ as a noun — ‘your running form’ — unconsciously biasing ourselves to think it’s a thing, an ideal that we should try to approach. It’s not a noun, though.

Pace (think sprinting versus end-of-ultra shuffling), terrain, angle of ascent or descent, time of month for some of you, fatigue level, today’s weight, weather, shoes, clothing, how far you’ve already run, what you did yesterday, surface wetness or dryness, texture, slipperiness, hardness/softness; the reader can add her or his own variations for influences. When enthusiasts instruct on perfect running form, they’re perhaps thinking, ‘Your perfect form when running on a flat unpitted moderately elastic non-slippery non-canted surface with neither wind nor rain nor snow nor excessive heat or humidity, neither speeding up nor slowing down nor turning, with no ground-level impediments nor larger obstacles nor other people nor animals near, nor any tree branches you might bump your head into, and after warming up, but not fatigued, while moving at your mid-high sustainable-for-a-few-minutes pace.’ Click-bait for sure.

§ § §

Of course there are plenty of people who are certain they know what that ideal is, the universal truth of running, and will with complete sincerity tell you. The word ‘natural’ is likely to show up.

This is scientifically unsound: any argument from evolution (nature) is descriptive, not prescriptive; feet are densely innervated nonlinear nonequilibrium dynamical systems that we don’t understand. ‘We evolved to run barefoot’ doesn’t stand up to the evidence that our intermarriage cousins the Denisovans were living on the Tibetan Plateau at least 170 thousand years ago. Human (Denisovan or Neanderthal) tools dating to 300 thousand years have been found in Siberia. Homo sapiens were in Mongolia 45 thousand years ago. We’ve been wearing shoes for a lot of generations. (Noting as well that evolutionary pressure would be centered on standing, walking, squatting, and stabilizing our trunks for throwing far more than on running.) Yes, running is part of our evolutionary heritage. That does not mean constant running without walking is a dominant evolutionary determinant, any more than is dancing, another human universal.

§ § §

Running is a skill, like dancing, so while your ‘perfect’ running form is something you have to continually rediscover from inside, looking at expert practitioners to see whether there are consistent patterns can (possibly) be helpful.

Here is Zola Budd winning the World XC Championship in 1986, running barefoot. She is a heel striker. (The gear icon at the bottom right of the YouTube frame allows you to adjust playback speed; slowing it down makes it easier to see.)

Kip Keino—the most beautiful runner I have ever personally seen—winning the 1968 Olympic Gold in one of the most strategically brilliant races of those or any other Games. Also a heel-striker, even at that extreme-for-us speed.

Sifan Hassan, the dominant runner of 2019, is a midfoot striker.

You can pick any number of elite runners, athletes who have immense volumes of running in their bodies, and find every form imaginable. Please don’t cite the third-dumbest paper published in the modern era under the Harvard brand name. Watch World Champion Tim Cheruiyot.

§ § §

It seems to be human to want a One True Way. It’s heroin to our minds for things to be simple. So here’s the One True Way to Perfect Running Form: Don’t interfere. Let your feet do what they want. They’re virtuosos. Enjoy feeling them.

TE Entries

The Tough Enough relay and the ultra will happen on Saturday, 04 April, 2020, starting at 7:00 am (relay) and ‘earlier’ for the ultrarunners, beginning at Toro Canyon Park, near Carpinteria, and finishing at Nojoqui Falls on the far side of Solvang. Teams comprise five or if necessary fewer runners, each running two (or more) legs. Advice for first-time teams (or anyone who wants a reminder) is on the Course Description page. The entry form is here.

Swag is now fully distributed.

Aching Bad (Marc L.)
Biscuits and Gravy (Erin McC.)
Call AMR (IRTC, Michelle M.) (Three-person team)
C.A.R.E. 4Paws (Isabelle G.)
Fun Bus Returns! (Sara K.)
Get-er-run (Katrin E.)
Hurt and Sole (Erin McC.)
Currently hypocognitive (Sten E.)
JMBLS (IRTC, Bonnie G.)
Modelos Not Coronas (IRTC, Sal S.)
No folly of the beasts of the earth (Molly T.)
Resolute in the jaws of destiny (Tracey M.)
Social Distance Runners (Lisa D.) (current leaders on topical team names)
Still trying to think (IRTC, Kim R.)
The Bald and the Beautiful (IRTC, Joe B.)
Team relay? I thought you said free buffet? (Spencer A.)
(IRTC => Inside Track Running Club)

Cooper Atkinson (glad to have you back!)
Rob DeCou
Rachel Entrekin
Martin Pattison
Mauricio Puerto (?)
Ian Seabury
Just Horrible Enough (IRTC, Karla & Billy)

TE19, TE20

Tough Enough gave $400 to Direct Relief International, which believes that while teaching a man (or woman) to herd sheep, shear, card, and weave wool may be great, if he or she is near death from cold just giving out a blanket is also great. (This is not their official motto.)

Course change for 2020: more dirt! Leg 2 will start and end at the same handoff points, but instead of E Mountain Drive and Gibraltar Roads, we’ll take West Cold Spring trail. Same fabulous gravitational pull, but worse footing! The trail emerges onto Gibraltar at the ‘180’ that’s been the handoff since the first running in 1986. The meeting point won’t change but the path between points will.

TE 2018

Tough Enough encompasses time, distance, and elevation change, riparian, meadow, oak forest, and mountain-top ecosystems, fire-scarred, flooded, and lush terrain, temperature ranges, and this year visibility varying from twenty feet to twenty miles. Thinking of all the things that have to be going right in our lives to be able to do this, it is extraordinary.

2018 Results

1 Weaver et al., 8:49
2 Who’s Running This Leg? 9:15
3 Are You Ruff Enough? 9:17
4 Austin Panthers 9:17
5 Pain Cave 9:28
6 Blister Sisters 9:32 (first all-woman)
7 A Bunch of Randos 9:45
8 Just Horrible Enough (ITRC) 9:46
9 The Galz 9:59
10 Otto Normalverbrauchers 10:07
11 Safety 3rd 10:15
12 Oh Truck, Where Art Thou? (ITRC) 10:21 (Wittiest name, hon. mention)
13 Kick Some Ash (ITRC) 10:56 (Wittiest name)
14 Happy Feet (ITRC) 11:09
15 Greg’s Groms 11:13
16 Four Girls and a Boy (ITRC) 11:19
17 Crossfit Oxnard 11:37

Karla and Billy of Just Horrible Enough were ‘distributed ultra’ runners, their alternating legs meaning each ran more than a marathon’s distance, and as a team impressively quickly. Ian Seabury was the sole full-length ultra entrant; he showed the common sense for which ultra runners are widely admired by dropping at the Gun Club with a potentially serious foot issue. Ian of course showed no sign of having run more than 50K when chatting with people at the finish.

Modest year for our annual contribution to Direct Relief International (though the event was in the black): $150.

2016 Donation to Direct Relief

The Tough Enough community — that’s you — donated $2,440 to  Direct Relief this year. Particular thanks to Mauricio and Leif for extra donations.

Please write to me or post comments with improvements or tuning you’d like next year. For example, one runner suggested having a 4WD patrol long, hot Leg 6 with water and snacks.

From the Race Director, thanks to Kimberly Burnell and Toad&Co.

On behalf of all of you, thanks to all of you.

TE 2016 notes

Luck. We were there at that time
Long sight from the ridge, over the chaparral, up through the pines
Later, in the valley, California poppies, lupine, wild mustard
Descending Refugio, oaks overhanging the trail, Spanish moss on north-facing hillsides
Sycamores tracking water


Good day. The noble-hearted Amigos de Goleta triumph. The JayKays have to wait another year in their attempt to dethrone We’ve Got The Fronk. How close? Sweet Stephanie and her cohort were roughly one-1000th of a percent faster. Ian and John looked not at all as though they’d just run 65 miles; Jon was graceful enough to look tired.

Sincere thanks to all runners and everyone supporting them. I feel fortunate in the opportunity to support you.

Accounting and donation to Direct Relief next weekend.

Results 2016

Commentary and accounting tomorrow.

12:23 Ian Seabury
13:23 John Hoenigman
14:20 Jon Zaid
Mauricio Puerto ran 55 but had to zip down to LAX.

08:18 Los Amigos de Goleta (Mr W. Rossow)
08:36 Why Not!? (Chris L.)
08:46 Trouble Follows Us (Ryan K.)
09:09 The Dillon Panthers (Mia G.)
09:12 We’ve Got the Fronk (Karen B.)

09:12 JayKay’s (Drat. Foiled again!) (Maggie and Kimberly)
09:13 Got the Runs (Oscar D.)
09:28 Inside Track (Kim) (possibly first women’s team?)
09:44 Team Three Generations (Scott Y.)
09:45 Wild Card! (Mike L.)

09:58 Inside Track (Rafael)
10:18 Right Turn Clyde (Matt K.)
10:38 Mount Those Twin Peaks (Eddie M.)
10:48 Without Adult Supervision (Simone K)
10:52 Delusions of Toughness (Valerie T.)

10:54 Atomic Force Awakens (Matt K.)
11:02 Ritardando (Whitney W.)
11:10 Inside Track (Galina)
11:22 Greg’s Groms (Greg L.)
11:29 Inside Track (Craig)

11:31 Inside Track: Joe
11:33 The Hills Have Cries (Jill C.)
11:38 Femmes Fa’trail (Katrin, Sara, Tara, and )
11:44 How Grandma Likes It (DR)
12:07 Inside Track (Erynne)

12:17 Conejos Chasing a Coyote (Diana P-M)

… but first, coffee. (Lauren D.; team ran half-way, had a family event)