CARDIOVASCULAR JOURNAL OF AFRICA • Vol 21, No 4, July/August 2010
198
AFRICA
to determine whether a significant difference existed between
pre- and post-tests. Differences in anthropometric measures were
compared using a one-way analysis of variance (ANOVA). When
significant differences were found at the post-test, a Dunnett
post
hoc
analysis was employed.
The control group’s data was utilised to calculate test–retest
reliability by quantifying it using the intra-class correlation
coefficient. Statistical significance was indicated by
p
≤
0.05.
Statistical analysis was performed with the Statistical Package
for Social Sciences (SPSS) version 14 (Chicago, IL).
Results
Mean pre- and post-training values are reflected in Table 2. The
NO, AT and CART groups were found to be statistically similar
at the start of the study regarding total cholesterol levels (
p
=
0.084), smoking status (
p
=
0.763), high-density lipoprotein
cholesterol levels (
p
=
0.201), systolic blood pressure (
p
=
0.339)
and FRA scores (
p
=
0.548).
The data indicated that while there was no change in total
cholesterol levels in the NO group from pre- to post-training
(
p
=
0.678), both the AT and CART groups were found to have
significantly (
p
<
0.05) decreased total cholesterol levels at post-
training (
p
=
0.004 and
p
=
0.007, respectively). Further
post hoc
analysis revealed that the aerobic and concurrent training had a
comparable effect on total cholesterol levels (
p
=
0.324) and that
both were more effective than no exercise (
p
=
0.004 and
p
=
0.008, respectively).
At the end of the 16-week period, there were no significant
differences in the number of cigarettes smoked by the three
groups. While the high-density lipoprotein cholesterol levels
of the NO group did not change (
p
=
0.672), the AT and CART
groups had increased high-density lipoprotein cholesterol levels
(
p
=
0.001 and
p
=
0.001, respectively). Aerobic training was
found to be as effective as concurrent training at increasing
high-density lipoprotein cholesterol levels (
p
=
1.000) and both
were more effective than no exercise (
p
=
0.030 and
p
=
0.005,
respectively). Sixteen weeks of aerobic and concurrent training
reduced systolic blood pressure (
p
=
0.049 and
p
=
0.002, respec-
tively). However, the NO group was found to have significantly
increased mean systolic blood pressure (
p
=
0.025).
Post hoc
analysis revealed that aerobic and concurrent train-
ing proved equally effective for improving systolic blood pres-
sure levels (
p
=
0.097). However, only concurrent training was
more effective than no exercise (
p
=
0.000). FRA scores were not
reduced in the NO group (
p
=
0.504), whereas both aerobic and
concurrent training proved effective in reducing their FRA scores
(
p
=
0.001 and
p
=
0.000). Aerobic and concurrent training were
found to be equally effective (
p
=
0.484).
Discussion
The FRA equation, which makes use of a group of variables rather
than a single variable, is an accepted method of estimating abso-
lute risk for CHD and is especially important in estimating the
10-year risk in adults who do not yet have CHD. Although most
research to date focuses on a single mode of exercise and how
it affects a single CHD risk variable, the present study provides
new data on how two modes of exercise training influence the
FRA scores of young adult males with few CHD risk factors.
We found that aerobic and concurrent aerobic and resistance
training had a favourable effect on levels of total cholesterol
and high-density lipoprotein cholesterol, systolic blood pressure
and FRA score. This is noteworthy, since concurrent training
decreased FRA score by the same amount as aerobic training
alone, despite the fact that the subjects who engaged in the
concurrent training did only half as much aerobic training as the
aerobic-only training group.
With regard to the effect of aerobic training on the individ-
ual variables determining the FRA scores, several studies have
found that this mode of exercise training had a favourable effect
on levels of total cholesterol
19-,22
and high-density lipoprotein
cholesterol,
4,17,20,23
and systolic blood pressure.
20,24
Although the
effect of aerobic training on the individual FRA variables is well
documented,
25
less is known about the effect of concurrent aero-
bic and resistance training.
26
The present investigation obtained
a seemingly novel result, with concurrent training resulting in a
significant reduction in total cholesterol levels. While this study
demonstrated increased high-density lipoprotein cholesterol
values following concurrent training, Wallace
et al.
27
did not find
significantly increased levels following their concurrent training
programme. Although their study supports the findings of the
present study, that concurrent training reduced systolic blood
pressure, the study of Pierson
et al
.
18
refutes these findings as
they found unchanged systolic blood pressure values following
concurrent training.
Conclusion
These findings are noteworthy since the addition of resistance
training to aerobic training can now be considered an alternative
and effective treatment to reduce the risk and prevalence of CHD
TABLE 2. CHANGES IN FRAMINGHAM RISKASSESSMENT SCORES FOLLOWINGAEROBICAND CONCURRENT
AEROBICAND RESISTANCE TRAINING IN HEALTHY PREVIOUSLY SEDENTARYYOUNGADULT MALES
Variables
Group
NO (
n
=
12)
AT (
n
=
12)
CART (
n
=
13)
Pre-training Post-training Pre-training Post-training Pre-training Post-training
TC (mg.dl
-1
)
195.75
±
10.49 194.83
±
11.85 173.67
±
29.93 161.75
±
26.78* 190.00
±
38.20 164.31
±
28.73*
Smoking status (cigarettes per day) 12.42
±
4.83 12.33
±
4.77 12.25
±
5.08 10.33
±
5.37* 12.00
±
4.71
8.77
±
5.10*
HDL-C (mg.dl
-1
)
49.33
±
6.34 50.17
±
8.97 47.00
±
11.85 57.50
±
5.99* 34.00
±
8.53
46.77
±
14.32*
SBP (mmHg)
122.00
±
5.72 124.67
±
4.77*
126.17
±
7.00 122.33
±
3.17* 131.54
±
9.28
121.69
±
7.87*
Total FRA score
5.00
±
2.80
4.67
±
2.46
3.58
±
2.19
1.33
±
2.27*
5.77
±
3.09
2.46
±
2.90*
TC: total cholesterol; HDL-C: high-density lipoprotein cholesterol; SBP: systolic blood pressure; FRA: Framingham risk assessment
*Significantly different when compared with pre-training values (
p
≤
0.05).
