Page 103 - JSOM Spring 2020

Recently, Vaara et al. reported that after 7 weeks of basic and of testosterone treatment was further modulated by the dura-
specialized training, neither body mass nor testosterone was tion of treatment.
affected in a group of 52 Finnish paratroopers. However,
5
in these same subjects, body mass and testosterone were de- Bhasin and colleagues used a high dose of exogenous testoster-
creased 2% and 47%, respectively, following a 5-day intensive one (600mg/weekly) in two separate studies, reporting a 4.6%
combat course. Similarly, Aakvaag et al. reported that a 6-day increase in LBM after 10 weeks and 12.3% after 20 weeks in
combat training course reduced testosterone levels 83%, simi- young adult males, suggesting that doubling the duration of
6
lar to the reduction reported after 8 weeks of Ranger training. the study increased the change in LBM. Interestingly, Kido
2
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Due to the significant reductions in LBM and testosterone that and colleagues used a low dosage of testosterone (~30mg/
occur within days of SOF training, the reductions in testoster- week) for 24 months. This dosage, well below the appar-
19
one on decreased LBM and impairments in muscle function ent effective threshold of 200mg/week, reportedly increased
appear to be related. LBM 12.2% after 24 months. Therefore, both the dose and
the duration of treatment appear to affect the increase in LBM.
Investigations on SOF during 3- to 5-day intensive train- In addition, the age of the subjects appeared to influence the
ing evolutions report very high EE of between 5,000 and effect of testosterone to increase LBM.
10,000kcal/day (Table 1). Aakvaag and colleagues reported
that EE in Norwegian cadets undergoing a 6-day combat The increase in LBM as a result of exogenous testosterone
course exceeded 10,000kcal/day. Similarly, a case report for treatment was markedly lower in older subjects (Table 2).
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an ultramarathon runner who ran continuously on a tread- Hildreth et al. recently reported that 12–24 months of tes-
mill for 24 hours indicated that he consumed ~13,000kcal. tosterone treatment in older men (66.5 ± 5.8 years) increased
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In highly fit males (maximal oxygen consumption ~ 65mL/kg/ LBM less than 2%. However, the dose used (~70mg/week) is
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min), testosterone levels decreased 37% when training volume less than the threshold of 200mg/week described here earlier.
was doubled for 2 weeks. This acute increase in training in- Frederiksen and colleagues treated older subjects (mean age 68
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creased EE associated with training by ~100%. Therefore, it years) with 350mg/week of testosterone for up to 6 months,
may be concluded that an acute increase in physical demand, reporting an increase in LBM of 2.6–2.8%. In contrast, Bha-
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resulting in an increase in EE, can reduce testosterone levels sin et al. used a similar dosage of testosterone (300mg/week)
in highly fit men. Training of SOF also results in a marked for 20 weeks and reported that LBM increased 8.2% in young
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increase in EE; however, SOF training also includes the addi- adult males (24 ± 5 years old). The response in younger men
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tional stress of a reduction in EI, resulting in a negative energy aged 20–30, specifically to increased LBM as a result of tes-
balance. tosterone treatment, appears to be far greater compared with
men ≥60 years old.
A negative energy balance may result from a reduction in EI,
an increase in EE, or a combination of the two. Although in- The average change for upper body and lower body strength
tense short-term (<8 days) SOF training results in EE of up to following testosterone administration was 7.9% and 16.1%,
10,000kcal/day, EI is reportedly as little as 1,600kcal/day, respectively (Table 2). Data on younger adult males (age 20–
3,6
resulting in an energy deficit (Table 1). Negative energy bal- 30 years) indicates that the change in strength, particularly
ances of 1,000–4,000kcal/day have also been reported during lower body strength, was related to the change in LBM. Lower
Ranger training. In these examples of SOF training, the neg- body strength may be more relevant to the demands of SOF
2
ative energy balance was accompanied by reduced testoster- who must carry heavy gear for prolonged periods. As reported
one levels. Similarly, during an acute 48-hour fast, where EI previously, LBM increased as a function of dose. Similarly,
was eliminated, the HPG axis was disrupted as evidenced by lower body strength increased more with increasing dosages
decreases in LH and testosterone of 27.5% and 34%, respec- (Table 2). For example, 20 weeks of 125mg/week testosterone
tively. Therefore, consistent with literature on fasting, the resulted in increases in LBM and strength of 2.9% and 6.1%,
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energy deficit that occurs in SOF training or SUSOPS is likely respectively, whereas 20 weeks of 300mg/week testosterone
an important factor in reducing testosterone. resulted in increased LBM and strength of 8.2% and 19.5%,
respectively. However, it should be noted that data do not
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On average, sleep during SOF training of 8 days or less is re- necessarily support a direct correlation between LBM and
portedly 2–4 hours/day and associated with decreases in tes- strength in older subjects.
tosterone (35–88%) and LBM (2–7%), as well as decreased
muscle function of up to 20% (Table 1). Similarly, a 1-week Testosterone and AAS in Diseased Populations
reduction in sleep from an average of 8 hours/night to 5 hours/
night reduced testosterone levels ~10%. This reduction was Testosterone
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independent of additional physical stress or negative energy Both testosterone and AAS have been used therapeutically to
balance indicating sleep deprivation as a key factor in reducing prevent cachexia, muscle wasting, and fatigue in patients living
testosterone during SOF training or missions. with HIV and chronic obstructive pulmonary disease (COPD),
as well as those undergoing dialysis (Table 4). Fatigue and di-
Testosterone minished work capacity, likely associated with cachexia and
Results indicate that LBM increased 6.2% following ~38 muscle wasting, are common symptoms in these populations,
weeks of testosterone treatment (Table 2). The magnitude of particularly those living with HIV. 18
the increase in LBM appeared to be a function of the dosage
of testosterone administered. In the studies reviewed presently, The use of exogenous testosterone (~150mg/week) for ~12
testosterone doses of <125mg/week reported increases in LBM weeks increased LBM and strength 4.1% and 12.7%, respec-
of ~2%. Dosages of ≥200mg/week to as much as 600mg/week tively (Table 4). Casaburi et al. incorporated resistance train-
increased LBM as much as 12%. Increased LBM as a function ing and 100mg/week of exogenous testosterone in a 10-week

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