The aim of the present study was to investigate the effect of a
14-week moderate intensity RT program on the maintenance
of BP and HGS during an extended detraining period in
older hypertensive sedentary women. Confirming the initial
hypothesis, after 14 weeks of detraining, SBP and MBP
remained statistically significant compared to pre-training
values, while the absolute HGS remained statistically significant
compared to the pre-training values. Besides, the
clinical significance demonstrated by the effect size remained
above 0.5 for the SBP, MBP, HGS, and HGS/kg. Only for
DBP was the effect small.
Although the ES is a measure of importance, it may
not be clinically relevant.34 We previously commented
that an ES above 0.5 was observed for SBP among other
variables, while a small ES was found for DBP. Despite the
low magnitude of DBP effect sizes during the detraining
period when compared to post-training, a small reduction
of 2 mmHg in the DBP and SBP could help prevent CAD
and stroke events.35,36
To the best of our knowledge, no previous study has
evaluated the effect of RT followed by a detraining period
on BP and HGS in elderly hypertensive sedentary women.
The results of the present study revealed that even after a
14-week detraining period following RT, hypertensive older
women were able to maintain the benefits on BP and muscular
strength. Recently, Moraes et al15 found a decrease of
16 mmHg in SBP of hypertensive middle-aged men after
12 weeks of RT. Moreover, the benefits of BP reduction
achieved with RT training were sustained for up to 4 weeks
without exercise. However, in contrast to the present study,
the population was middle-aged men (46±3 years), with a
shorter detraining period of 4 weeks and participants had all
antihypertensive medications gradually withdrawn. The study
by Moraes et al15 is the only one that evaluated the effects
of detraining (4 weeks) on BP in hypertensive individuals.
Despite the clinical effect found (decreased BP sustained),
the effects of RT cessation on BP without a washout period
(medication withdraw) in elderly hypertensive women were
poorly understood
The potential mechanisms underlying the reduction and
maintenance of BP following the detraining period have been
previously studied. Some proposals indicate that reduction
in peripheral vascular resistance by a decline in cardiac output,
a release of vasoactive factors, an increase in baroreflex
sensibility, and greater participation in physical activities
unrelated to RT might be involved.16
For muscular strength, although measured by hand grip,
our results are in accordance with previous results that
show elderly individuals display decreased neuromuscular
performance after a period of detraining, but retain higher
values than pre-training levels. Correa et al37 performed
a similar longitudinal protocol using elderly women that
consisted of twelve weeks of an RT program twice a week
followed by twelve weeks of detraining. The results of this
study found that strength gains were partially maintained
following the detraining period. Lovell et al38 found similar
results in older men following four weeks of detraining.
Furthermore, previous studies have shown that the muscular
strength of elderly individuals, when subjected to
RT of moderate to high intensity, can be maintained above
baseline levels during 12 to 48 weeks of detraining.16,17
Although, similar results were found for muscular strength,
it is difficult to compare the data collected in this study
with other studies because tests that involve one or more
maximum repetitions were not utilized and the intensity
control during the training period was made by participant
self-report using an RPE scale, which results in higher
intersubject variability.
The accurate measurement of muscle strength requires
expensive equipment, and the results have low applicability
when compared to simple measures of muscle strength
utilizing HGS. HGS is strongly associated with muscle power
and force of the lower limbs in older persons, and is relatively
practical, reproducible, and inexpensive.13 In addition, HGS
is considered an important predictor of functional capacity,
cardiovascular disease, cancer, mortality, dementia, and
nutritional state in elderly people.8,11,39
The present study has some limitations. According to
Lauretani et al,13 HGS is appropriate to monitor the effectiveness
of systemic treatments, both pharmacological and
nonpharmacological, aimed to improve muscular strength.
However, exercise interventions may have a more variable
impact on different muscle groups and should be monitored
with appropriate regional measures. Additionally, our analysis
was made in the absence of a control group, so flaws in the
causal relationships should be considered. Moreover, salt
intake and hydration status were not controlled, although participants
were advised to maintain their normal dietary habits
during the study. During the training period, the intensity of
RT was individually controlled by the participants utilizing an
RPE scale. This strategy may not have normalized the relative
effort in the group, because each participant has a different
interpretation of their exertion level. Furthermore, the presence
of heterogeneity in medications used by our subjects
might have introduced bias in our hemodynamic results.
Despite the limitations, our findings raise interesting
ideas for future research trials, such as the investigation
of periodization, volume, intensity, and training frequency
which may contribute to the maintenance and control of
muscular streng