Strength Training as a Supplemental Therapy of Androgen Deficiency of the Aging Male (ADAM)
Phase: NA
Conditions: Hypogonadism, Male, Physical Activity, Testosterone Deficiency
Sponsor: Comenius University

 
 
 
 
 
 
Strength training as a supplemental therapy for androgen 
deficiency of the aging male (ADAM): Study protocol for a three-
arm clinical trial. 
 
 
NCT03282682 
 
 
23.03.2020 
 
 
 
 

Aims 
The overall aim of the trial is to examine the effect of a 12-week strength training 
program with and without TRT on body composition, physical function, selected biochemical 
markers of metabolic health, histological and molecular parameters and the quality of life of 
patients with ADAM. 
 
Study design 
The study is a clinical trial with three arms comparing the effect of strength training with 
testosterone replacement therapy (ST + TRT), strength training alone (ST) on hypogonadal 
males and on a control group of healthy eugonadal males (HM), also engaged in strength 
training for 12 weeks.  
 
Trial status  
At the time of the first submission of the protocol, the trial was in the phase of participant 
recruitment. The recruitment began in February 2017 and the last part of data collection is 
expected to end in August 2019.  
Participants 
 
Subjects will be included from urological units at Department of Urology, University 
Hospital-Petrzalka, Bratislava, Slovakia; Department of Urology, Faculty of Medicine, 
Comenius University, Bratislava, Slovakia and 5. Department of Internal Medicine, Faculty of 
Medicine, Comenius University, Bratislava, Slovakia. The study will involve in total sixty-six 
male participants divided into three groups (n = 66): group 1, males with hypogonadism who 
are undergoing testosterone replacement therapy (TRT) (n=22); group 2, newly diagnosed 
males with hypogonadism without testosterone replacement therapy (NON-TRT) (n=22); 
group 3, healthy eugonadal men (HM) (n=22). The participants from all groups engaged in 
strength training. The volunteers are screened for testosterone levels before the start of the 
participation by the specialist. 
The most important inclusion criteria for participation in the study from the patient 
population are age 40-60 years old, subjects with hypogonadism on TRT or newly diagnosed 
patients of hypogonadism. The hypogonadal patients fulfilling the criteria for study 
participation will be verified for low testosterone before entering the study. The same 
verification will take place at the end of the study. The most important exclusion criteria include 
regular strength training, conditions that are medical contraindications and prostate cancer or 

abnormal serum PSA levels without adverse histological examination. All inclusion and 
exclusion criteria are listed in Additional file 1. In addition to written information, eligible 
subjects will be verbally informed about the study by their responsible urologist and the study 
officials before participation. TRT provided to patients is intramuscular (IM) injection of 
testosterone undecanoate (TU) at a dose of 1000 mg repeated every 12 weeks. Testosterone 
undecanoate (Nebido) is the only injectable form of testosterone used at the institutes of 
collaborating physicians of the study. According to our knowledge, this form of T at dose of 
1000 mg is the most stable of all available preparations for 3 months’ period, which is 
considered a standard treatment in Slovakia. Shorter-acting forms may cause more pronounced 
fluctuations in 24-hour circulating levels of testosterone. The participants will be asked to not 
change their habitual dietary intake and physical activity patterns. Participants will be asked to 
continue in physical activities as before, but any kind of regular physical activity, especially 
strength training or any other kind of weight training during the intervention will be also 
prohibited. The exclusion criteria reject any participant, who performed any kind of regular 
strength training one year prior to study. 
 
Strength training intervention 
 
The strength training protocol will be a modified strength exercise program from Segal 
et al. [61] which was used in similar group of patients. The participants will perform 24 training 
sessions of strength training protocol with the frequency of two training sessions per week for 
12 weeks. There will be at least 48 hours rest period between two subsequent training sessions 
(Monday and Thursday). The intervention will take place at the Faculty of Physical Education 
and Sport, Comenius University in Bratislava, Slovakia. All training sessions will be supervised 
and guided by professionals with university degree in sports training to ensure safety, correct 
technique and progression in training load, with a maximum of three participants per one 
trainer. The participants will be familiarised with the equipment and exercise technique one 
week before the start of the intervention. The technique corrections will be possible during the 
whole intervention if needed. Ten repetition maximum (RM) and 12RM diagnostic test for all 
exercises will be conducted during the first week of training intervention.  
 
Each training session will include a 5-minute dynamic warm-up, consist of 10 exercises 
for approximately 30 seconds of each, and exercises will be focused on main muscle groups 
(Table 2).  
 
 

Table 2: Dynamic warm-up 
Dynamic warm-up exercises 
Number of repetitions 
Walking low skip 
Walking high knee skip 
Walking knee to chest 
Walking hamstring stretch 
Walking lunge 
Standing lateral lunge 
Egyptian mobility exercise 
External rotation exercise 
Hip hinge exercise 
Air squat  
8 times each leg 
8 times each leg 
8 times each leg 
6 times each leg 
6 times each leg 
6 times each leg 
6 times each arm 
6 times each arm 
8 times 
8 times  
 
The strength protocol exercises will be performed with free weights and on machines. The 
training program consist of six exercises for upper and lower body at an intensity of 60-80% (8 
– 12RM: the load that induces technique failure in eight or twelve repetitions) of one-repetition 
maximum and takes approximately 60 minutes. The inability to perform full repetition will be 
assessed by a supervisor or by participants’ feedback. The participants will be instructed to 
perform a concentric action for 2 seconds and immediately after an eccentric action also for 2 
s. There will be 90 seconds rest period after each set. The same duration rest period will be 
between all of the exercises. The rest periods will be controlled by timer (The miniMAX, 
Gymboss, USA). The load will be added, if participant can complete prescribed number of 
repetition in each set of the exercise. More detailed strength training protocol can be seen in 
Table 3. During the first three weeks of the intervention, there will be one set in the beginning 
with light weight to focus on safety and technique. After that three more sets with weight close 
to 60 – 80 % of 1RM will follow. After first three weeks, the number of sets will be increased 
to four.  
Table 3: Strength training protocol 
Week 
Number 
of 
exercises 
Number 
of 
sets 
Number 
of 
repetitions 
Resistance 
Rest 
period 
Tempo 

1 – 3. week 
3+3 (UB, LB) 
3 
10-12 
10-12RM 
90s  
2:0:2:1 
4 – 6. week 
3+3 (UB, LB) 
4 
10-12 
10-12RM 
90s 
2:0:2:1 
7– 9. week 
3+3 (UB, LB) 
4 
6-8 
6-8RM 
90s 
2:0:2:1 
10 – 12. week 
3+3 (UB, LB) 
4 
6-8 
6-8RM 
90s 
2:0:2:1 
 
UB – upper body, LB – lower body, RM – repetition maximum, Tempo – duration in seconds 
during the repetition -  2s (eccentric): 0s (end range of the motion): 2s (concentric): 1s (rest 
between repetitions in the starting position)  
 
The exercises performed during every session will be: leg press, split squat, bench press. The 
exercises alternating through the week are knee extension with leg curl, seated row with seated 
pull down and incline dumbbell bench press (training equipment provided by KOHI Leopoldov, 
Slovakia and Technogym, Italia). Since unilateral exercises (e.g. one leg squats) develop similar 
magnitude of muscle activity with producing less load on the spine, thus they are safer [62], the 
split squats are chosen instead of regular squats. Prescribed exercises in the strength training 
protocol for every training sessions can be found in Table 4. Each session will be supervised 
by at least two professionals, who received strength training programme and record every 
repetition and set made in each session in an individual training plan. At the start of each 
session, the trainers will ask participants if they experienced any adverse events since the last 
session and record reported events. All adverse events during the training session will be written 
down into paper spread sheet and processed afterwards. Each training session will be monitored 
with an attendance list, with minimum 85% attendance during the study. Each session will be 
marked as successfully completed when at least 80% from the total volume and intensity of the 
training protocol planned for the particular training session is performed. If a participant will 
be unable to perform any of the exercises or sets, this will be recorded into a prepared training 
plan and the situation will be managed during the first week during familiarization with the 
training protocol. The appropriate alternative exercise will be considered depending on the 
restriction or participant’s limitation.  
 
Table 4: Training sessions, type of exercises and type of resistance 

1st training session 
Type of resistance 
2nd training session 
Type of resistance 
Split squat 
Bench press 
Leg press 
Seated row 
Leg curl 
Lateral raise 
Dumbbells 
Barbell 
Machine 
Machine 
Machine 
Dumbbells 
Bench press 
Split squat 
Incline press 
Leg press 
Pull down 
Knee extension 
Barbell 
Dumbbells 
Dumbbells 
Machine 
Machine 
Machine 
 
Clinical outcomes 
Clinical outcomes will be collected one week before the intervention (pre-intervention 
assessments) and one week after the intervention (post-training assessments). All outcomes, 
specific variables and assessments in each testing are listed in Additional file 2. All participants 
will be tested at the same time of the day, and asked to avoid caffeinated and alcohol beverages 
before the assessments. 
  
 
Familiarization 
To secure validity of the physical tests, all subjects undergo a session of familiarization 7 days 
prior to the intervention assessments. All sessions are performed based on the same guidelines, 
but after the familiarization session the load of each resistance exercise will be adjusted to 
match the expected maximum.   
 
Primary outcome measure   
Lean mass (LM) 
The primary outcome of the study will be the change in lean mass (LM) measured by Dual-
energy X-ray Absorptiometry (Hologic fan-beam bone densitometer Discovery QDR series). 
The changes in lower and upper body LM are analysed separately because of differences in 
androgen sensitivity in leg muscles compared to neck, chest and shoulder muscles [63]. Due to 
very similar results but greater participant comfort [63] we decided to use The National Health 
and Nutrition Examination Survey (NHANES) protocol, which required the participant to be 
positioned in a supine position in the middle of the densitometry table with head straight, space 
between the arms and torso, palms flat on the table, and feet together secured by a strap. The 

systematic review of Shiel et al. [64] showed a strong level of agreement as illustrated by high 
ICC's and CCC's between the Nana and NHANES positioning protocols, however systematic 
bias within limit of agreement plot and a large difference in 95% confidence limits indicates 
that the protocols should not be interchanged when assessing an individual.  
 
Secondary outcome measures 
Body composition 
 
Other body composition parameters (fat mass, total body mass) will be measured at the same 
time so also the protocol is the same as with the primary outcome.  The height will be measured 
by stadiometer and waist circumference will be measured by stretch-resistant tape that provides 
a constant 100 g tension. The body mass index is afterwards calculated and reported. 
 
Muscle strength 
 
 
Muscle strength of lower extremities will be measured as force production during maximal 
voluntary contraction (MVC) isometric knee extension and isometric knee flexion knee 
dynamometer (ARS dynamometry, S2P ltd., Ljubljana, Slovenia). Each of the test will be 
performed 6 time with three practise trials and three recorded trials. For the first practise trial, 
participants will be instructed to achieve approximately 50% of the maximum, with 20 seconds 
rest period. The second and third practise trial will be performed at 80% of the maximum with 
20 second rest periods. The last three trials will be performed with maximal voluntary effort 
and  will be recorded. The best out of three will be taken for further analyses. Rest period during 
recorded trials will be 60 seconds. During the MVC, the participants will be asked to push/pull 
as strong as possible and hold for five seconds. Intra-session repeatability for MVC is the 5.7 
CV % and 0,98 ICC. Additionally, with awareness of health issues (such as higher blood 
pressure) and because of a safety reasons, dynamic leg press 1RM (one repetition maximum) 
will be predicted from multiple repetition maximum testing [65].  
For assessing the muscle strength of the upper extremities, the isometric MVC handgrip 
strength will be measured by Camry Digital Hand Dynamometer. The participant will stand 
upright and holds the dynamometer in the hand next to the body, with the minimal or none 
flexion in the elbow joint. The base of the handle will be on the first metacarpal, while the 
handle should rest on the middle of the four ringers. None of the body parts will be allowed to 
move. The test will be performed with three practise trials. First on 50% and the others on 80% 

of their perceived maximum with 20 seconds’ rest period. After that, three maximum trials with 
rest period of 60 seconds will be recorded and the best out of three will be taken for further 
analyses.  The participants will be encouraged to give their maximum effort. The participant 
will squeeze the dynamometer for 5 seconds. After the test with dominant hand, the test will be 
performed for non-dominant hand.  
Cardio-respiratory fitness 
Cardio-respiratory fitness will be measured by The Single Stage Treadmill Walking Test [66], 
where the participants will be asked to walk on Pro Treadmill (Woodway, USA). During the 
walking test, participants will wear same shoes they will use during the whole intervention. The 
speed during the test can be changed if needed. The procedure will be performed once and 
heartbeat will be tracked by heart rate monitor attached on the chest. VO2max will be calculated 
according the literature [66]. 
10-m preferred walk-speed and 10-m maximum walk-speed will be measured by timing gates 
WITTY GATE (MicroGate, Italy). Participants will walk 10 meters and the time will be 
measured for the intermediate 6 meters. This allow acceleration and deceleration. The gates 
will be placed on 2-meter mark and 8-meter mark. The timing starts when participant cross the 
first mark and stop when the 8-meter mark is crossed. There will be three trials for preferred 
and three trials for maximum walk-speed.  The outcome measure will be velocity in meters per 
second calculated as mean of the three trials or the best trial from the preferred and maximum 
walk-speed test, respectively. Participants will be asked to perform at preferred walking speed 
first followedand then at the fastest walking speed possible. 
Psycho-social functioning 
 
 
 
The general health status will be measured by The Short Form (36) Health Survey 
patient-reported survey of patient health (SF-36). In addition, clinically investigating the health-
related quality of life (HRQoL) symptoms of aging men are measured by Aging Males' 
Symptom (AMS) Scale. The AMS scale had internal consistency [α = 0.89 (95% CI 0.88-
0.90)]; the mean alpha estimates across the AMS subscales ranged from 0.79 to 0.82. The AMS 
scale also had good test-retest reliability [r = 0.85 (95% CI 0.82-0.88]; the test-retest reliability 
coefficients of the AMS subscales ranged from 0.76 to 0.83 [67]. AMS is a standardized scale 
according to psychometric norms. Most of the currently available language versions were 

translated following international standards for linguistic and cultural translation of quality of 
life scales. [68].  
 
 
Serological outcomes  
 
Fasting morning venous blood will be taken after overnight (10-hour) fasting and 15 min rest 
from cubital vein from 8:00 am to 10:00 am [69] into closed system collection tubes containing 
beads coated with a clotting activator and polyacryl ester-gel (Sarstedt AG & Co, Germany). 
The blood will be centrifuged (3000g, 4°C, 10min) immediately after sampling to obtain EDTA 
plasma or they will be centrifuged (3000g, 4°C, 20min) after 30min at RT, to obtain serum. The 
haematological and biochemical parameters analyzed immediately will be haemoglobin, 
hematocrit, leucocytes, thrombocytes, glucose, urea, sodium, potassium, calcium, ALAT, total 
cholesterol, LDL cholesterol, HDL cholesterol, triglyceride, testosterone, oestrogen, LH, FSH, 
SHBG, albumin, bilirubin, total protein, CRP, insulin and PSA. Plasma and serum aliquots (500 
ul) will be stored at -20°C (analysis within 6 months) and at -80°C for the long term storage.  
Bioactive molecules (myokines, exerkines, released from skeletal muscle and/or other tissues) 
which could be associated with the adaptive response to exercise in all patients will be 
quantified.        
 
Muscle cellular outcomes 
 
 
Muscle biopsies will be obtained from approximately 80% of the subjects included in the study. 
Subjects not willing to undergo biopsy are still eligible for trial participation. 
 
 
With the subject in a supine position, a 5 mm Muscle Biopsy Cannula (Bergstrom-Stille, 
Sweden) with manual suction is used to obtain muscle samples (200 mg), under local 
anaesthesia (Lidocain 2%). Before the intervention, the biopsy will be obtained from the mid-
section of the right m. vastus lateralis, and after the intervention the biopsy will be obtained 3 
cm proximal to the pre-intervention biopsy.  
 
Muscle fibre size and regulators of muscle fibre size  
Muscle fiber size, measured as muscle fiber cross sectional area, represents the primary muscle 
cellular outcome. Secondary muscle cellular outcomes reflecting regulators of muscle fibre size 

are a) number of myonuclei per muscle fiber b) number of satellite cells per muscle fiber, c) 
number of satellite cells and myonuclei positive for androgen receptors and d) proteins involved 
in muscle protein degradation (muscle breakdown). The number of satellite cells will be 
quantified on frozen muscle cross sections with a immunohistochemical protocol as described 
in Bjornsen et al. [70] (Pax7 + Laminin + DAPI). 
 
Muscle fibre cross sectional area and regulators of muscle fibre size are analysed by 
immunohistochemistry on cross sections of muscle biopsies and by western blots and enzyme-
linked immunosorbent assay (ELISA) in muscle homogenate.  
Muscle fibre cross sectional area is measured by cutting transverse serial sections of the muscle 
biopsy (8 µm thick) with a cryostat microtome (Microm, Germany) at -22°C and mounted on 
glass slides. Serial sections are immunohistochemically stained for fibre types (type I and type 
II) (used to measure muscle fibre cross sectional area), number of satellite cells, number of 
myonuclei and number of satellite cells and myonuclei positive for androgen receptors. Muscle 
fibre cross sectional area is measured for the different fibre types separately. 
Statistical Analysis 
Normality of the data distribution will be assessed by comparing histogram of the sample data 
to a normal probability curve and outliers will be identified as values distant for more than 3σ 
from the average.  Normality will be further tested with Kolmogorov-Smirnov test if needed.   
Differences between normally distributed variables will be evaluated by the Analysis of 
variance with repeated measures and Bonferroni post-hoc test, differences between pre- and 
post-training values of the specific subpopulation will be evaluated with a paired Student’s t-
test. Non-normally distributed variables will be log transformed. Variables that could not be 
log transformed to normal distribution will be tested with non-parametric tests (Mann-Whitney 
test and Wilcoxon rank test). 
Cohen’s d will be used to calculate effect size (ES), represented by ‘d’ and interpreted as < 0.2 
is a small, 0.2-0.8 is a moderate, and > 0.8 is a large effect size. 
For studying the relationships between the various outcomes, the Pearson or Spearman 
correlation tests will be used. 
All statistics were performed using a statistical software Statistical Package for the Social 
Sciences (SPSS) 21.0 (IBM Inc., Armonk, New York, U.S.,) and p values < 0.05 will be 

considered significant. Data will be presented as means and standard deviations. Missing 
endpoint data will disqualify patient from the endpoint analysis. Missing single value, of 
training progression records will be replaced by the last observed value. 
 
Background variables 
Information about medical situation as time points for treatment and stage of symptoms are 
collected from the medical record. Past illnesses and other medical problems are also reported 
in the questionnaire.  
Patients and public involvement 
Patients (study participants) will be informed about the individual results of the baseline 
examination as well as on the primary and secondary outcomes of the study, in a form of 
individual consultation with a research team member.  
Patients or public (patient organizations) were not involved in the development of the research 
question or study design. However, they will be asked to help with recruitment, and will also 
be involved in the conduct of the study with the power to shape (individualize) the training 
intervention according to individual preferences, prior experiences and medical conditions. 
Moreover, they will be involved in individualizing the follow-up intervention protocol, shaping 
thus the long-term exercise programme to increase its sustainability.      
Sample size  
The pre-existing data from our previous 12-week exercise intervention study related to fat 
(5.6% decrease p=0.002) & lean body mass (1.8% increase, p=0.047, DXA) and that of 
maximal voluntary contraction force measured on linear leg-press (31% increase, p<0.0001, 
1RM). Lean body mass was used to determine sample size for the population of the designed 
intervention study. The Type I error probability was set at 0.05 and the power to 0.90 and 0.95. 
Results indicate that 22 patients per group will be sufficient to detect exercise intervention 
related change of 1,06 ± 1,56 kg (average ± SD) of lean body mass at the power of 0.90, 
accounting for the 10% patients drop-out. 
 
Ethics and Dissemination  

This trial was approved by Ethics Committee of the University Hospital in Bratislava, Slovakia 
(ref. trial number: 127/2017). All the participants will be fully informed on the study protocol 
risks and benefits and will provide the written informed consent prior entering the study. 
Participation in the trial is fully voluntary.  Inability to comply with the study protocol will not 
affect the healthcare. Data will be stored and handled anonymously using the coding system 
complying with the General Data Protection Regulation 2016/679. All unexpected, serious 
adverse events will be reported to the study sponsor as well as to the relevant health insurance 
company within 7 days. The findings of this trial will be published in peer review journals, 
scientific conferences with main audience of healthcare professionals, healthcare providers, but 
also patients and their families. Trial was registered at ClinicalTrials.gov: NCT03282682. 
 
AUTHORS’ CONTRIBUTIONS  
MK, JC, TR, MS participated in the study design and drafted the manuscript, GB participated 
in the development of the intervention protocol, TR, BU and JU designed protocol for 
biological sample collection and processing, and will participate in biological material sampling 
& analyses. MP, ZK, JP, BK and PB provide access to patients. MK, MS, JC, JU and MK 
performed data analysis. All authors contributed to and approved the present manuscript.  
 
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Funding statement 
 
The study is funded by the Scientific Grant Agency of the Ministry of Education, Science, 
Research and Sport of the Slovak Republic and of the Slovak Academy of Sciences (VEGA) no. 
1/0714/16.  
 
Competing interests statement 
 
We declare that we have no significant competing financial, professional, or personal interests 
that might have influenced the performance or presentation of the work described in this 
manuscript.