J. S. Gottschall et al. / Open Journal of Preventive Medicine 3 (2013) 132-140 133
at least 3 days per week, or a combination of these mod-
erate- and vigorous-intensity regimens 3 - 5 days per
week. In addition, the position stand recommends that
adults engage in a full body muscular strength routine 2
days per week as well as flexibility exercises 1 - 2 days
per week.
Past research demonstrates that implementing an exer-
cise program with both cardiovascular activities and
strength training, without any dietary changes, can re-
duce cardiovascular disease risk factors. Park et al. [5]
compared the data from a group of participants who
completed a 24-week combination cardiorespiratory and
strength training protocol to both a cardiorespiratory
training only protocol and a control group. The combined
training program was the most effective in reducing
CVD risk factors as mean body fat percentage decreased
by 11.2%, LDL-C decreased by 34.7%, and triglycerides
decreased by 42.3% from baseline. In addition, HDL-C
increased by 23.1% and lean body mass increased by
10.3%. In a similar study, Libardi et al. [6] studied inac-
tive participants who completed concurrent cardiorespi-
ratory and strength training for 16 weeks in comparison
to three other study groups; resistance training only, car-
diorespiratory training only, and a control group. Similar
to previous reports, the combined protocol yielded the
most significant results whereby total cholesterol con-
centration decreased by 27.8% and triglycerides de-
creased by 33.4%. McCarthy et al. [7] also evaluated the
effects of a concurrent training program on sedentary
men for a 10-week training program of cardiorespiratory
and full body strength training. Total body weight did
not statistically decrease, however fat percentage de-
creased from 19.5% to 17.2%.
These studies found significant changes in cardiovas-
cular disease risk factors by combining cardiorespiratory
and strength training into one exercise program. The
current study augments the approach by utilizing a group
fitness program that mimics the Physical Activity Guide-
lines for Fitness. A Nielsen survey of over 3000 partici-
pants in group fitness classes across the globe showed
that more than 85% of these members visit their clubs at
least 2 days per week specifically to engage in classes
and nearly 43% of these members visit their club 4 times
a week for this purpose [8]. To add, the International
Health, Racquet and Sportsclub Association (IHRSA)
estimates that United States club members attend their
gyms 3.4 times a week to attend group fitness classes [9].
Thus, group fitness may be one method to minimize at-
trition and thereby maximize health benefits in a com-
prehensive and holistic manner. We hypothesize that a
30-week multimodal group fitness intervention will pro-
duce beneficial effects on CVD risk factors by reducing
body weight, total cholesterol, LDL-C, triglycerides
concentration, systolic blood pressure, diastolic blood
pressure, and by enhancing lean body mass percentage,
HDL-C, glucose tolerance and maximal oxygen con-
sumption.
2. METHODS
Twenty-nine healthy adults, 18 women and 11 men,
started the program and 25 participants, 15 women and
10 men (Figure 1, Table 1) finished the program. All of
the participants gave written informed consent that fol-
lowed the guidelines of The Pennsylvania State Univer-
sity Human Research Committee. The participants were
physically inactive, but otherwise healthy, and completed
a health exam at the beginning of the study to determine
if physical activity was appropriate. The initial inclusion
criteria for the study was for the participant to be be-
tween the age of 25 and 40, completing less than 30
minutes of exercise per week for the previous 6 months,
and available from May to December without more than
four days of travel in a single week. We excluded poten-
tial participants from the study, in accordance to the
ACSM health screening for physical activity, if he or she
had any of the following conditions: chest discomfort
with exertion, unreasonable shortness of breath, symp-
toms of dizziness, fainting or blackouts, heart medication,
asthma or other lung disease, burning or cramping sensa-
tions in lower legs with minimal physical activity, joint
problems that limit physical activity, prescription medi-
cations, pregnancy, diabetes, smoking, blood pressure
greater than 140/90 mmHg, or total blood cholesterol
greater than 220 mg·dL−1.
2.1. Laboratory Measurements
We collected musculoskeletal and physiological data
at baseline (Week 3), midpoint (Week 19) and final
(Week 31) time points of the study. The majority of the
measures were collected at the university Clinical Re-
search Center such as height, weight, blood pressure,
blood concentrations and body composition variables.
Blood was drawn from the antecubital vein after a
48-hour alcohol and a 12-hour food fast. The samples
were assayed (Quest Diagnostics, Pittsburgh, PA) with a
24-Chem analysis, which included total cholesterol,
LDL-C, HDL-C, triglycerides, and glucose. Body com-
position measurements were collected using a total-body
scanner (GE Lunar iDXA, Madison, WI). Scan analysis
was performed using GE Encore 11.10 software. This
software allows for adjustment of regions of interest in-
cluding the sagittal line, which controls the left-right
body distribution of tissue.
Immediately following this research center visit, we
conducted a submaximal oxygen consumption test on a
treadmill at the Biomechanics Laboratory. We measured
the rates of oxygen consumption (VO2) using an open
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