Specimen readout

Your genotype

GG · Ala/Ala (study CC)TMPRSS6 is on the - strand. Studies report T (Val736) / C (Ala736) on the gene strand; consumer files show A (= T, Val) and G (= C, Ala). A file 'AA' is the study's 'TT'. The literature numbers this residue 736 (A736V); Ensembl's canonical transcript numbers it 727.

Matters at

Orientation wk 1–7 · NSWO (running volume)Also Pre-Hell Week and Post-Hell Week (running volume); Land warfare (running volume and loaded rucking)

Reading

Both copies carry the allele associated with higher serum iron and transferrin saturation.

Consider

No genetic flag. Heavy training can still lower iron stores.

We won't claim

That you are anemic or iron deficient (only blood tests show that), anything about iron overload, or any supplement dose.

Sources: Benyamin et al. 2009, Nat Genet · doi:10.1038/ng.456

Your genotype

TT · XXC = R (577Arg, makes alpha-actinin-3); T = X (577 stop codon, no alpha-actinin-3). ACTN3 is on the + strand, so file letters match the literature. The reference base differs by genome build (GRCh37 T = X, GRCh38 C = R), so whole-genome VCF calls are converted from REF/ALT to letters; 0/0 is never read as RR.

Matters at

Orientation wk 1–7 · NSWO (soft-tissue load)Also Pre-Hell Week and Hell Week (cold water and soft-tissue load); Combat diving (cold water); Land warfare (soft-tissue load)

Reading

Neither copy makes alpha-actinin-3. In one cold-water immersion study of 42 young men, XX held core temperature better than RR, by raising muscle tone rather than shivering. XX is less common among power athletes, and a 2026 systematic review of small studies linked it to more muscle and soft tissue injury.

Consider

Train to the program. The cold-water finding comes from one study and does not replace progressive cold-water exposure. Consider building eccentric strength (downhill running, loaded lowering) gradually.

We won't claim

That you are a 'power' or 'endurance' type, that you will tolerate cold water better or get injured more, that this genotype decides any event, or anything about your chance of finishing selection.

Sources: Chelly et al. 2025, J Strength Cond Res (meta-analysis, 90 studies) · doi:10.1519/JSC.0000000000005192Wyckelsma et al. 2021, Am J Hum Genet · doi:10.1016/j.ajhg.2021.01.013Abboud et al. 2026, Genes (systematic review) · doi:10.3390/genes17020212

Your genotype

AG · I/D (by proxy)Consumer chips cannot read the 287-bp Alu insertion/deletion itself (rs1799752). rs4343 tags it in Europeans (D' = 1, r2 = 0.88, n = 64): A marks I (insertion), G marks D (deletion). The tag has been validated only in European-ancestry samples and is not a reliable I/D proxy in African ancestry: G is 20% in 1000 Genomes Africans against 57% in Europeans, and the validating paper notes that rs4343 and I/D track plasma ACE differently in Africans. ACE is on the + strand.

Matters at

Orientation wk 1–7 · NSWO (running volume)Also Pre-Hell Week and Post-Hell Week (running volume); Land warfare (running volume and loaded rucking)

Reading

One insertion and one deletion copy. This is the most common genotype in European-ancestry samples and sits between I/I and D/D in the studies cited. This proxy was validated in European-ancestry samples only.

Consider

Train to the program. This genotype gives no reason to change the balance of strength and endurance work.

We won't claim

That you suit or don't suit any pipeline, how you will respond to training volume, or anything about blood pressure or heart health. Effects are small and many studies found no association.

Sources: Montgomery et al. 1998, Nature · doi:10.1038/30374Woods et al. 2001, Hum Genet · doi:10.1007/s004390100466Abdollahi et al. 2008, Dis Markers (rs4343 as I/D proxy) · doi:10.1155/2008/813679

Your genotype

CT · Gly/SerPPARGC1A is on the - strand. The gene-strand G (Gly482) / A (Ser482) appear in consumer files as C (Gly) / T (Ser).

Matters at

Orientation wk 1–7 · NSWO (running volume)Also Pre-Hell Week, Post-Hell Week and Land warfare (running volume)

Reading

One copy of each. The study cited compared allele counts, so it gives no separate reading for heterozygotes.

Consider

Train to the program.

We won't claim

Anything about your VO2max, diabetes or metabolic health, or that this genotype caps your aerobic fitness.

Sources: Lucia et al. 2005, J Appl Physiol · doi:10.1152/japplphysiol.00037.2005

Your genotype

CC · S/S (study GG)COL1A1 is on the - strand. Studies report G (S) / T (s) on the gene strand; consumer files show C (= G, S) and A (= T, s). A file 'AA' is the study's 'TT'.

Matters at

Orientation wk 1–7 · NSWO (soft-tissue load)Also Pre-Hell Week, Hell Week and Land warfare (soft-tissue load)

Reading

Both copies are the common S form, the reference genotype in the studies cited.

Consider

Train to the program; progress running, rucking and jumping load gradually.

We won't claim

That your ligaments or tendons are strong or weak, anything about bone density or osteoporosis, or your chance of a specific injury.

Sources: Posthumus et al. 2009, Br J Sports Med · doi:10.1136/bjsm.2008.056150Fukuyama et al. 2025, Int J Sports Med (meta-analysis, athletes) · doi:10.1055/a-2419-4359Ryan-Moore et al. 2020, Front Genet (meta-analysis, active people) · doi:10.3389/fgene.2020.00551

Your genotype

TT · T/TCOL5A1 is on the + strand; file letters match the literature (C/T).

Matters at

Orientation wk 1–7 · NSWO (soft-tissue load and running volume)Also Pre-Hell Week and Land warfare (soft-tissue load and running volume); Hell Week (soft-tissue load); Post-Hell Week (running volume)

Reading

Both copies T. In pooled studies of mostly European-ancestry cohorts, TT carried about 1.6 times the odds of Achilles, ACL and elbow tendon injuries. A 2025 meta-analysis limited to athletes found no association.

Consider

Consider a slow ramp in run and ruck mileage and regular calf and hamstring strength work, and get persistent tendon pain looked at early.

We won't claim

That you will get a tendon or ligament injury, or anything about joint hypermobility conditions.

Sources: September et al. 2009, Br J Sports Med · doi:10.1136/bjsm.2008.048793Lv et al. 2018, Oncotarget (meta-analysis) · doi:10.18632/oncotarget.23805Fukuyama et al. 2025, Int J Sports Med (meta-analysis, athletes) · doi:10.1055/a-2419-4359

Your genotype

CC · Glu/Glu (study GG)MMP3 is on the - strand. Studies report G (Glu45) / A (Lys45) on the gene strand; consumer files show C (= G) and T (= A). A file 'CC' is the study's 'GG'. SNPedia displays this SNP on the gene strand (A/G).

Matters at

Orientation wk 1–7 · NSWO (soft-tissue load and running volume)Also Pre-Hell Week and Land warfare (soft-tissue load and running volume); Hell Week (soft-tissue load); Post-Hell Week (running volume)

Reading

In one case-control study, this genotype had about 2.5 times the odds of Achilles tendinopathy, and risk rose further together with the COL5A1 rs12722 T allele. A 2025 meta-analysis of athletes found no association.

Consider

Consider progressing run and ruck volume gradually and including calf strength work. Read this together with COL5A1.

We won't claim

That your tendons will fail, or anything about joint disease.

Sources: Raleigh et al. 2009, Br J Sports Med · doi:10.1136/bjsm.2008.053892Fukuyama et al. 2025, Int J Sports Med (meta-analysis, athletes) · doi:10.1055/a-2419-4359

Your genotype

GT · G/TGC is on the - strand. SNPedia and some papers use the gene-strand letters A/C; consumer files show T (= A) and G (= C). G is the allele associated with lower blood 25(OH)D.

Matters at

First Phase wk 1–3 · Pre-Hell Week (bone load)

Reading

One copy of G, the allele associated with lower blood 25(OH)D in a genome-wide study of 33,996 people.

Consider

Consider asking your physician about a serum 25(OH)D test well before you ship.

We won't claim

Your actual vitamin D level (only a blood test shows that), that you will get a stress fracture (vitamin D variants did not track bone changes in 2,550 Army trainees), or any supplement dose.

Sources: Wang et al. 2010, Lancet (GWAS, 33,996 people) · doi:10.1016/S0140-6736(10)60588-0Gazdzinska et al. 2026, Nutrients (331 soldiers) · doi:10.3390/nu18183041Roberts et al. 2026, J Appl Physiol (2,550 Army trainees) · doi:10.1152/japplphysiol.00181.2026

Your genotype

GG · G/GReported on the + strand in the GWAS and in consumer files. A is associated with higher 25(OH)D, G with lower.

Matters at

First Phase wk 1–3 · Pre-Hell Week (bone load)

Reading

Both copies carry the allele associated with lower 25(OH)D in genome-wide studies of up to 79,366 people. On its own the effect is small.

Consider

If GC or DHCR7 also point low, consider asking your physician about a serum 25(OH)D test before you ship.

We won't claim

Your vitamin D level, your fracture risk, or any supplement dose.

Sources: Wang et al. 2010, Lancet (GWAS, 33,996 people) · doi:10.1016/S0140-6736(10)60588-0Jiang et al. 2018, Nat Commun (GWAS, 79,366 people) · doi:10.1038/s41467-017-02662-2Fernandez-Lazaro et al. 2025, Int J Mol Sci (CrossFit athletes) · doi:10.3390/ijms26125602

Your genotype

TT · T/TReported on the + strand in the GWAS and in consumer files. T is associated with higher 25(OH)D, G with lower.

Matters at

First Phase wk 1–3 · Pre-Hell Week (bone load)

Reading

Both copies carry the allele associated with higher 25(OH)D. This is the most common genotype in Europeans.

Consider

No genetic flag here.

We won't claim

Your vitamin D level, your fracture risk, or any supplement dose.

Sources: Wang et al. 2010, Lancet (GWAS, 33,996 people) · doi:10.1016/S0140-6736(10)60588-0Jiang et al. 2018, Nat Commun (GWAS, 79,366 people) · doi:10.1038/s41467-017-02662-2

Your genotype

TT · Ile/IleWNT16 is on the + strand; file letters match the GWAS. C (Thr) is associated with thinner cortical bone and lower forearm bone density, T (Ile) with thicker and higher. SNPedia displays this SNP on the opposite strand (A/G); consumer files and the GWAS use C/T.

Matters at

First Phase wk 1–3 · Pre-Hell Week (bone load)

Reading

Both copies carry the allele associated with thicker cortical bone and higher bone density.

Consider

No genetic flag. Bone still adapts slowly, so progress impact and load gradually.

We won't claim

That you will get a stress fracture, or anything about osteoporosis. Bone density can only be measured with a scan.

Sources: Zheng et al. 2012, PLoS Genet · doi:10.1371/journal.pgen.1002745

Your genotype

CC · Ala/AlaLRP5 is on the + strand; file letters match the literature. C = Ala1330, T = Val1330.

Matters at

First Phase wk 1–3 · Pre-Hell Week (bone load)

Reading

The common genotype and the reference in the studies cited.

Consider

No genetic flag. Progress impact and load gradually.

We won't claim

That you will get a stress fracture, or anything about osteoporosis.

Sources: van Meurs et al. 2008, JAMA (37,534 people) · doi:10.1001/jama.299.11.1277Ryan-Moore et al. 2020, Front Genet (meta-analysis, active people) · doi:10.3389/fgene.2020.00551

Your genotype

AC · Glu/AlaP2RX7 is on the + strand; file letters match the literature. A = Glu496 (normal receptor), C = Ala496 (loss of function). SNPedia displays this SNP on the opposite strand (G/T); consumer files show A/C.

Matters at

First Phase wk 1–3 · Pre-Hell Week (bone load)

Reading

One loss-of-function copy. In one report, the Ala496 allele was associated with stress fracture in 210 Israeli military conscripts (43 with stress fractures) and again in 518 athletes. No independent group has repeated it.

Consider

Consider ramping running and rucking volume gradually, avoiding sudden jumps in weekly load, and getting shin or foot pain checked early.

We won't claim

That you will or won't get a stress fracture.

Sources: Varley et al. 2016, Purinergic Signal (military conscripts and athletes) · doi:10.1007/s11302-016-9495-6Herbert et al. 2022, Eur J Appl Physiol (endurance runners) · doi:10.1007/s00421-021-04789-z

Your genotype

AG · Ala/ThrP2RX7 is on the + strand; file letters match the literature. G = Ala348, A = Thr348 (gain of function). SNPedia displays this SNP on the opposite strand (C/T); consumer files show G/A.

Matters at

First Phase wk 1–3 · Pre-Hell Week (bone load)

Reading

One gain-of-function copy; same association as above, in one study.

Consider

No change. Progress load gradually.

We won't claim

That you are protected from stress fractures.

Sources: Varley et al. 2016, Purinergic Signal (military conscripts and athletes) · doi:10.1007/s11302-016-9495-6

Your genotype

CC · C/CFKBP5 is on the - strand, but the literature, dbSNP and SNPedia name this intronic SNP by its + strand letters (C/T), the same letters consumer files report. T is the minor allele studied in the literature (about 31% in 1000 Genomes Europeans).

Matters at

First Phase wk 1–3 · Pre-Hell Week (acute stress)Also Hell Week and Combat diving (acute stress)

Reading

The common genotype. Cortisol returned to baseline normally after a standard lab stress test.

Consider

No genetic flag.

We won't claim

Anything about PTSD, depression or mental health risk, or how you will handle stress. This is a stress-hormone marker only.

Sources: Ising et al. 2008, Eur J Neurosci · doi:10.1111/j.1460-9568.2008.06332.x

Your genotype

CT · C/TADORA2A is on the + strand; file letters match the literature (T/C). Older papers number the same SNP differently (1976T>C, 1083T>C).

Matters at

First Phase wk 4 · Hell Week (caffeine response, placed where sleep loss falls)

Reading

One copy of each. C carriers reported less caffeine-induced anxiety than TT; in a twin study, the odds of caffeine-related insomnia rose with each C copy.

Consider

If caffeine is already part of your routine, note how it affects your sleep. Discuss any change in use with your physician.

We won't claim

Anything about anxiety disorders or mental health, or how much caffeine to take.

Sources: Rogers et al. 2010, Neuropsychopharmacology · doi:10.1038/npp.2010.71Childs et al. 2008, Neuropsychopharmacology · doi:10.1038/npp.2008.17Retey et al. 2007, Clin Pharmacol Ther · doi:10.1038/sj.clpt.6100102Byrne et al. 2012, Sleep (2,402 twins, caffeine-related insomnia) · doi:10.5665/sleep.1962

Your genotype

CT · C/TReported on the + strand in the GWAS and in consumer files (T = 38% in the GWAS, 39% in 1000 Genomes Europeans). C is associated with higher habitual caffeine intake, T with lower.

Matters at

First Phase wk 4 · Hell Week (caffeine response, placed where sleep loss falls)

Reading

Intermediate; a very small effect on habitual intake.

Consider

No genetic flag.

We won't claim

How much caffeine you should use. This locus explains under 1% of the difference in intake between people.

Sources: Cornelis et al. 2011, PLoS Genet (GWAS meta-analysis) · doi:10.1371/journal.pgen.1002033

Your genotype

AC · A/CCYP1A2 is on the + strand; file letters match the literature. A is the higher-inducibility allele often called 'fast'.

Matters at

First Phase wk 4 · Hell Week (caffeine response, placed where sleep loss falls)

Reading

Intermediate. In the 101-athlete study, caffeine had no effect on 10-km cycling time in AC; the 2024 meta-analysis found a small benefit.

Consider

If caffeine is already part of your routine, note how it affects your sleep and training. Any change in use is a decision for you and your physician.

We won't claim

That caffeine will or won't help you, how much to take, or anything about heart health.

Sources: Sachse et al. 1999, Br J Clin Pharmacol · doi:10.1046/j.1365-2125.1999.00898.xGuest et al. 2018, Med Sci Sports Exerc (101 athletes) · doi:10.1249/MSS.0000000000001596Barreto et al. 2024, Med Sci Sports Exerc (meta-analysis, 13 studies) · doi:10.1249/MSS.0000000000003313

Your genotype

AG · Val/MetG = Val, A = Met on the + strand as reported by 23andMe/Ancestry. COMT is on the + strand, so the literature uses the same letters.

Matters at

First Phase wk 4 · Hell Week (sleep loss)

Reading

Intermediate enzyme activity. Val carriers as a group lost more of their ability to adapt when task rules reversed during total sleep deprivation; rested, there was no difference.

Consider

Practise making decisions while tired, and rehearse procedures until they hold up when you are depleted.

We won't claim

Anything about intelligence, personality, stress 'type' or mental health. We don't use 'warrior gene' labels, and this does not predict selection.

Sources: Satterfield et al. 2018, Cortex · doi:10.1016/j.cortex.2017.11.012

Your genotype

AG · G/ATNF is on the + strand; file letters match the literature (G common, A less common).

Matters at

First Phase wk 4 · Hell Week (sleep loss)

Reading

One copy of -308A. In 88 adults kept awake in the lab, A carriers lost less reaction-time vigilance during total sleep deprivation, and a follow-up study of 12 people (4 A carriers) repeated the result. Both studies came from the same research group. The genotype explained under 10% of the difference between people.

Consider

Vigilance still falls with sleep loss. Don't trust feeling alert; keep checklists and buddy checks.

We won't claim

That you can safely go without sleep, or anything about inflammatory disease.

Sources: Satterfield et al. 2015, Brain Behav Immun · doi:10.1016/j.bbi.2014.12.009Skeiky et al. 2020, Chronobiol Int · doi:10.1080/07420528.2020.1821044

Your genotype

CC · G/G (study)ADA is on the - strand. Studies report G (Asp8) / A (Asn8) on the gene strand; consumer files show C (= G) and T (= A). A file 'CT' is the study's 'G/A'.

Matters at

First Phase wk 4 · Hell Week (sleep loss)Also Post-Hell Week (recovery)

Reading

The common genotype, with typical adenosine breakdown. It is the reference group in the sleep studies cited.

Consider

No genetic flag. Sleep loss still costs everyone.

We won't claim

Anything about sleep disorders or immune conditions.

Sources: Retey et al. 2005, Proc Natl Acad Sci USA · doi:10.1073/pnas.0505414102Bachmann et al. 2012, Cereb Cortex · doi:10.1093/cercor/bhr173

Your genotype

CT · Val/MetBDNF is on the - strand. The gene-strand G (Val66) / A (Met66) appear in consumer files as C (Val) / T (Met).

Matters at

First Phase wk 4 · Hell Week (sleep loss)Also Post-Hell Week (recovery)

Reading

Met reduces activity-dependent BDNF release. In one small study, Val/Met showed less training-driven change in motor cortex responses to brain stimulation; in another (22 people), Val/Met had less deep sleep than Val/Val. These are lab measures of brain activity and sleep, not of performance.

Consider

Train to the program. These findings give no basis for a different plan.

We won't claim

Anything about intelligence, memory, mood or mental health.

Sources: Kleim et al. 2006, Nat Neurosci · doi:10.1038/nn1699Bachmann et al. 2012, Sleep · doi:10.5665/sleep.1690