How Much Physical Activity Is Needed To Maintain Erectile
Function? Results of the Androx Vienna Municipality Study
Christian W. Kratzika,*, Jakob E. Lacknera, Isabel Ma ¨rka, Ernst Ru ¨cklingerb,
Jo ¨rg Schmidbauera, Gerhard Lunglmayrc, Georg Schatzla
aDepartment of Urology, Medical University of Vienna, Vienna, Austria
bStatistical analysis and Methodological Consulting KEG, Vienna, Austria
cDepartment of Urology and Karl Landsteiner Institute of Andrology, Mistelbach General Hospital, Mistelbach, Germany
erectile function (EF) and what can be done about it.
Age, diabetes, and hypertension are important risk
factors of ED. Lifestyle factors, including PhA and
nutrition, may also negatively impact EF. However,
lifestyle factors can be modified and, commonly,
patients who intend to be treated for ED undergo
counseling by the physicians to stop smoking and
european urology 55 (2009) 509–517
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Accepted February 26, 2008
Published online ahead of
print on March 5, 2008
Objective: To assess the correlation of erectile function (EF) and physical
activity (PhA) by using standardized, validated instruments in healthy
Methods: A urologist examined 674 men aged 45–60 yr at their place of
work. That included a urological physical examination, medical history,
and assessment of testosterone (T) and sex hormone–binding globulin;
all men completed the 5-item International Index of Erectile Function
(IIEF-5) as well as the Paffenbarger score. PhA was assessed in kilojoules
per week (4.2 kJ = 1 kcal).
Results: A positive correlation between the IIEF-5 and the Paffenbarger
score (r = 0.164, p < 0.001) was found. The IIEF-5 score increased with an
increasing Paffenbarger score up to a level of 4000 kcal/wk. T revealed a
trend to a significant impact on the IIEF-5 score, but showed no associa-
tion with the Paffenbarger score. The risk of severe erectile dysfunction
(ED) was decreased by 82.9% for males with PhA of at least 3000 kcal/wk
compared with males with PhA under 3000 kcal/wk (OR = 0.171,
p = 0.018).
Conclusion: Increasing PhA from 1000 to 4000 kcal/wk may reduce the
risk of ED.
# 2008 European Association of Urology. Published by Elsevier B.V. All rights reserved.
* Corresponding author. Department of Urology, University of Vienna, Waehringer Guertel
18-20, 1090 Wien, Austria. Tel. +43 1 40400 2636; Fax: +43 1 87775498.
E-mail address: firstname.lastname@example.org (C.W. Kratzik).
0302-2838/$ – see back matter # 2008 European Association of Urology. Published by Elsevier B.V. All rights reserved.doi:10.1016/j.eururo.2008.02.020
lose weight. It has been clearly documented in
previous studies that PhA may prevent ED, specifi-
cally in the aging population. Indeed, the question of
how much exercise is required to maintain EF still
on the amount of PhA needed to maintain EF.
There are numerous reports about the benefit of
much exercise men should do. In these reports the
International Index of Erectile Function (IIEF) score
was generally used to obtain comparable and valid
data on the EF; however, for the evaluation of PhA,
the methodology was insufficient. Ponholzer et al 
less than once a week. Detailed description of the
kind of PhA is missing; thus, it is not clear if the PhA
was sports activity such as endurance activity,
strength sport, or maybe only walking. To address
this source of error, we used an objective evaluation
of PhA in this study, namely the Paffenbarger score,
which assesses PhA in kilojoules per week.
Thus the objective of this study was to clarify
possible links between PhA and ED, and to further
elucidate the quantity of weekly exercise required to
The data presented in this paper originate from The Androx
Vienna Municipality study, a voluntary health status program
offered to men aged 45–60 yr who were employed by the
Vienna Municipality as manual workers involved in energy
supply and public transport [3–5]. The study was approved by
the Karl Landsteiner Institute Quality Control Board.
The Vienna Municipality employs about 2400 men in that
study age group as manual workers. A total of 752 men (31% of
thosepossibly eligiblefor this study) agreedto participate, and
674 men were included in the final analysis. Exclusion criteria
consisted of psychopharmacological medication (eg, benzo-
diazepine), antihypertensive drugs (eg, beta-blocker), medica-
tion possibly affecting the endocrine function, any medication
for ED, and a history of previous pelvic trauma. Because an
abnormal urogenital status (eg, Peyronie’s disease, cryptor-
chism, testicular atrophy, prostate cancer) may have an
impact on EF, men with these conditions were also excluded
from this study. Because it is generally accepted that diabetes
can be a dominant factor for ED, all patients with diabetes
were excluded from this study. After the above-mentioned
exclusion criteria were applied, a total of 674 men remained
for analysis and were entered into this study. Details of the
demography of these men are shown in Table 1.
All participants were investigated at their place of work and
were fit for work at the time of investigation. General health
statusandlife stylewereassessedby a standardizedinterview
including queries on general lifestyle, smoking (number of
(number of beer, wine, hard drinks consumed per day), and
diabetes. Diabetes was excluded on the basis of a medical
history assessment that included questions about risk factors
and urine testing for glucose. Each participant received the
questionnaires about 1 week before the scheduled visit. At the
scheduled visit, the questionnaires were reviewed by an
investigator to insure that all questions were answered. Body
weight and height were measured. Between 8:00 and 10:30 AM,
two blood samples were drawn from the antecubital vein for
assessment of blood chemistry and endocrine levels. Blood
samples were frozen until analyzed. Each subject had a
complete urological examination by a trained urologist who
assessed the genital area (size and position of testicles,
palpation of penis, etc) and a rectal examination. Assessment
of prostate-specificantigenandurine analysiswas performed.
The same laboratory performed all hormonal assessments.
were measured by an electrochemiluminescence immunoassy
Germany). Sex hormone–binding globulin (SHBG) was mea-
sured by immunometric assay (IMMULITE1 2000 SHBG,
Diagnostic Products Corporation, Bad Nauheim, Germany).
For evaluation of bioavailable testosterone (BAT), we used the
equation published by Bartsch et al .
2.4. Physical activity
PhA was assessed with the Paffenbarger Score . This score
measures PhA in kilojoules per week (4.2 kJ = 1 kcal) using
average walking distance (km/d), number of floors climbed,
and sports or recreational activities as criteria. The frequency
(weeks per year) and duration (time per week when active) of
each activity or sports were reported by the participants.
Kilojoules per week resulting from number of floors climbed,
average walking distance, and all sports or recreational
activities were summed and categorized into <500, 500–999,
1000–1999, 2000–2999, 3000–3999 and >4000 kcal/wk.
In addition, the type and intensity of PhA were investi-
gated. A multiple of resting metabolic rate (MET score) was
assigned for each activity . We separately calculated and
categorized energy expenditure from vigorous (?6 MET score),
moderate (4 to <6 MET score), and light (<4 MET score)
activities . Vigorous energy expenditure is represented, for
example, by fast walking (4.5 mph/h), moderate by (3 mph/h),
and light by walking around at home or in the office.
2.5. Erectile function
EF wasassessedwith theIIEF-5score,whichmeasureserectile
function and the severity of erectile dysfunction (ED). ED was
classified according to the definitions of Rosen et al  as
mild ED (17–21), and no ED (22–25).
european urology 55 (2009) 509–517
[OR] = 1.7 [1.5–2.0]) and who lived a sedentary
lifestyle (OR = 0.7 [0.7–0.8] for subjects with physi-
cal activity >32.6 metabolic equivalent of energy
expenditure in a resting state [MET] per week
versus <2.7 MET/wk). Accordingly, Giuliano et al 
demonstrated that decreasing BMI and increasing
exercise significantly improved ED in approxi-
mately one-third of cases. Early endothelial dys-
function and impaired nitric oxide synthesis,
necessary to stimulate smooth muscle relaxation
and increased blood flow necessary for erection,
have been considered the major pathogenetic
associated issues .
Until now, no study has been available showing
how much exercise is required to maintain erectile
function. Kratzik et al  should be congratulated
for their report. They demonstrated for the first
time that erectile function can be maintained with
an energy expenditure of as little as 1,000 kcal/wk.
The link between obesity and ED might be a useful
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activity is needed to maintain erectile function? Results
of the Androx Vienna Municipality Study. Eur Urol
DOI of original article: 10.1016/j.eururo.2008.02.020
european urology 55 (2009) 509–517