Effects of aerobic and resistance training on hemoglobin A1c levels in patients with type 2 diabetes

This article examines the effects of aerobic and resistance training on hemoglobin A1c levels in patients with type 2 diabetes. The study includes a randomized controlled trial with a focus on the population of men and women in Louisiana who lead a sedentary life and suffer from type 2 diabetes mellitus with high HbA1c levels. The interventions include resistance training, aerobic exercise training, and a control group with no exercise. The outcomes measured include changes in HbA1c levels, anthropometry, and fitness. The study concludes that a combination of aerobic and resistance training is most effective in reducing HbA1c levels.

Running head: CASP
PICO Question
P (Population) Suffering from type 2 diabetes mellitus
I (Intervention) Physical activity
C (Comparison) No physical activity
O (Outcome) Improvement in the disease state of diabetes mellitus
Question
Whether practice of physical activity helps in improving the overall disease state of
type 2 diabetes mellitus (T2DM)?
Article selected
Church, T.S., Blair, S.N., Cocreham, S., Johannsen, N., Johnson, W., Kramer, K., Mikus,
C.R., Myers, V., Nauta, M., Rodarte, R.Q. and Sparks, L., 2010. Effects of aerobic and
resistance training on hemoglobin A1c levels in patients with type 2 diabetes: a randomized
controlled trial. Jama, 304(20), pp.2253-2262.
Critical analysis tool
CASP tool for RCT

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Answer 1
Yes.
The article highlighted that main population of interest over which the analysis is required to
be undertaken and this include men and women in Louisiana who led a sedentary life and is
suffering from T2DM with high HbA1c.
The main interventions given to the population include resistance training for 3 days a week
for one group (72 individuals) and another group (72 individuals) to aerobic exercise training
(12 kcal/kg per week and rest 76 individuals (10 kcal/kg per week) are given combined
aerobic and resistance training.
The comparison was done with the control group (no exercise control group).
The outcomes that are considered include change in the HB1c level and the secondary
outcomes are anthropometry and fitness.
Thus, the issue is focused with all the important term of the assignment.
Answer 2
Yes.
Health Benefits of Aerobic and Resistance Training in individuals with type 2
diabetes (HART-D) study was randomized for 9-month of exercise intervention with a
control group. Initially 2421 individuals were screened for the eligibility. Of them 1139 were
excluded (declines, non-diabetic, enrolled to other studies, taking medications and exceed the
preferred age). 1282 were found eligible of them finally 262 were selected for the final study.
Among them 41 were included to the control group and rest in the study group. The division

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of 262 participants in the experimental and the control group was done randomly and the
allocation sequence was concealed from researchers and the patients. According to Opie
(2019), randomization of the participants in the RCT study helps to improve the outcome of
the results by reducing the selection bias.
Answer 3
No.
All the patients who entered in the trial, do not accounted for its conclusion. This is
because, in the control group (41), 4 lost follow-up, in the randomized group to resistance
training (73), 5 participants lost follow-up). In the group of randomized to aerobic exercise
training (72), 3 lost to take part in the follow-up session and the number of 5 for the
randomized to combination exercise group (76). Thus, the total of the 262 participants, only
245 complete the study. Moreover, the level of adherence of the physical exercise was less in
70 % among some of the participants of the experimental groups. Thus, though the trial was
not stopped early, but the follow-up session lead to participants’ dropout and thereby
reducing the overall strength of the study. The patient analyzed in groups. However, the
analysis was based on intent-to-treat analysis and per-protocol analysis.
Answer 4
No.
Members of the HART-D scientific advisory committee recommended that the
placebo group is required to be monitored stringently. Safety monitoring of the control group
included blinded monitoring of the levels of HbA1c. The blinding of the placebo group was
withdrawn after seven of the participants of the placebo group (17.1%) experienced increase
in the level of HbA1c by 1.0% or higher. However, the separate intervention and the

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assessment teams who were used for the analysis of the results ere blinded to the participants
randomization assignment. Thus, the study is single blinded randomized control trial.
According to Teare et al. (2014) double blinded randomized control trail score more in the
domain of reliability and validity of the study in comparison to the single blinded trial. The
unbinding of the placebo group might lead to the generation of placebo effects.
Answer 5
Yes.
All the groups were similar before the initial of the trial. During the initial of the trial
first 1139 prospective individuals who were screened were excluded from 2421 group. Apart
from excluding the declined o non-interested group, the screened individuals were excluded
if they were non-diabetic, average age not meeting 55.8 years, BMI not meeting the limit of
greater than/equals to 48.0. The main criteria for the selection of the participant include both,
women of them 63% are women, and 47.3% were nonwhite participants. The age group of
the participants resides with the average bar of 55.8 years with a baseline HbA1c level of
7.7%. The individuals who lead a sedentary life were only included in the study. Teare et al.
(2014) are of the opinion that having uniform inclusion criteria for recruiting of the
individuals in the RCT helps to increase the validity of the study. Having the same
demographic characteristics of the individuals in the RCT helps to get uniform baseline data
and thus reducing the level of bias.
Answer 6
Yes.

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The main experimental interventions used in the study are physical exercise. In the
physical exercise section, all the three experimental group under-went exercise of
approximately 140 minutes per week. The entire physical exercise session was designed
based on the 2008 Physical Activity Guidelines. In the subsequent follow-up, the main
parameter that was measured was reduction in the HbA1c in comparison to the baseline level.
The follow-up sessions also measured the level of fitness and anthropometry. According to
Esposito et al. (2015) apart from physical exercise, proper management of the high blood
sugar level in diabetes can be done by observance of the anti-diabetic diet that is less in
calorific count and is high on protein. Increase in the intake of carbohydrate in the diet plan
along with increase in the consumption of sugar leads to an increase in the overall blood
sugar level and this is reflected in the increase in the level of HbA1c. In this study, the author
collected the baseline data of the diet of the selected group of participants based on the Block
Food Frequency Questionnaire. The same questionnaire was used to ascertain the diet chart
of the participants (both experimental and control group) during the follow-up session. The
authors are of the opinion that the use of the self-reported questionnaire limits the ability to
access the changes in the diet composition and the calorie intake. Guerrero et al. (2015)
highlighted that the use of the self-reported questionnaire mainly leads to the generation of
the biased outcome and the main bias attributed for this is personal bias. Thus, though the
authors attempted equal treatment of the participants during and after the follow-up.
However, the use of the self-reported questionnaire for the assessment of diet creates a gap in
accessing whether all the participants followed the same diet plan during the entire follow-up
session. Moreover, the follow-up session also failed to take into account of the fact that
whether the selected group of participants (both control and experimental group) was
conducting any additional exercise apart from the designed experimental activities. These can

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be regarded as the confounding factors modulating the overall effect of the study (James, Rao
and Granger 2015).
Answer 7
The selected RCT study included both primary and secondary outcome. The primary
outcome of the study includes change in the level of HbA1c. The secondary outcome of the
study includes measurement of the anthropometry and fitness. Thus, it can be said that the
primary outcome of the study is clearly specified. The measurement of the primary outcome
of the study was compared with the baseline data in order to highlight the significant
deviation. The result of the outcome highlighted that though both resistance and aerobic
training was helpful in fetching benefits, the combination of both the exercise was successful
in fetching maximum amount of benefit with significant reduction in the Hb1Ac level. The
cumulative benefit across all the outcomes was found higher in the combination physical
exercise training in comparison to the aerobic exercise or resistant exercise training. The
results were highlighted for each of the outcome of the study. In order study the level of
fitness and anthropometry, proper assessment was conducted in domain of session workout
per week, the percentage of the trade-mill grade, trade-mill speed, the tenure of aerobic
exercise, weight lifted and the daily steps counted. Thus, the overall treatment effect were
large. According to James, Rao and Granger (20150, in order to structure a stringent RCT
study, both the primary and the secondary outcome of the study must be tabulated in detail
with a detail explanation in the discussion section.
Answer 8
All the results of the study are presented in the form of least squares that are adjusted
with 95% of the confidence intervals (CIs). CI is plus-or-minus figure and is used denote the
level of surerity of the evaluate result. According to Hemming et al. (2015), CI interval is

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used to denote how reliable the test result is. The CI of 95% highlights that the replication of
the evaluated result in any other selected set of population is 95%. This help to increase the
overall reliability and generalizability of the result. Hemming et al. (2015) are of the opinion
that wider is the confidence interval, it is more certain that the same result will be extracted
from another true percentage of population. Thus, selection of the 95% of the confidence
interval help to highlight that the overall study is reliable.
Answer 9
Yes
The result is applicable to a wide range of the local population. This is because, The
main target population that was selected for the conduction of the study include the adults
with an average age group of 55 to 58 years. According to Jaacks et al. (2016), the detection
of the type 2 diabetes mellitus is common among the population who are above 40 years of
age. The rate of occurrence is same between both men and women. Thus, selection of the age
group of 55 years (on an average) helped to increase the generaisability of the research. The
selection of the participants was done from different ethnicity including white, African
Americans and Hispanic. According to Jaacks et al. (2016), the rate of occurrence of the
diabetes mellitus is higher among the African Americans and Hispanic population. Smoking
history also included under the consideration both current and former smoker were included
in the selection group. Jaacks et al. (2016) are of the opinion that smoking is one of the
modifiable risk factor behind the development of type 2 diabetes mellitus. Other factors,
which are taken under the consideration during the selection of the target population, include
high BMI, high waistline and high level of HbA1c. Garg et al. (2014) stated in their study
that high body weight or obesity along with increase in the overall blood glucose level are the

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main risk factor behind the development of type 2 diabetes mellitus. Sedentary lifestyle was
also taken into account during the selection of the candidate.
Thus, the selection of the target population for the study was done based on the main
modifiable risk factors under the diabetes development and thus it can be said that results can
be applied to the local population.
Answer 10
Yes.
All the clinically important outcomes were considered in the study that is reduction in
the level of the HbA1c level in the blood along with increase in the muscle dextreousness
were compared in order to denote reduction in the severity of the diabetes mellitus under the
effect of the physical activty. However, the authors also failed to measure whether the
conduction of the physical activity was effective in reduction in the body weight of the
individuals with sedentary life. According to Tobias et al. (2014), physical exercise is
regarded as one of important parameter to study the reduction in the body weight. Reduction
in the body weight is also regarded as an important parameter in reduction in the severity of
the diabetes mellitus. However, the author failed to study how the conduction of the physical
activity helped to reduce the body weight. Ascertain this aspect of the type 2 diabetes mellitus
will be helpful in optimal evaluation of the study in the domain of the effectiveness.
Answer 11
Yes.
The benefits are worth of harms or costs. Nope of the participants of the study is
harmed. No significant adverse effect of the study was highlighted in the selected group of

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the participants. Williams and Thompson (2014) are of the opinion that regular practice of the
physical activity like aerobic and resistance is not associated with any significant negative
effects on the body unless or until the person is suffering the cardio-vascular complications.
The authors of this RCT study excluded the individuals who were suffering from the chronic
healthcare conditions and thus reducing the possible chances of negative effects.

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References
Church, T.S., Blair, S.N., Cocreham, S., Johannsen, N., Johnson, W., Kramer, K., Mikus,
C.R., Myers, V., Nauta, M., Rodarte, R.Q. and Sparks, L., 2010. Effects of aerobic and
resistance training on hemoglobin A1c levels in patients with type 2 diabetes: a randomized
controlled trial. Jama, 304(20), pp.2253-2262.
Esposito, K., Maiorino, M.I., Bellastella, G., Chiodini, P., Panagiotakos, D. and Giugliano,
D., 2015. A journey into a Mediterranean diet and type 2 diabetes: a systematic review with
meta-analyses. BMJ open, 5(8), p.e008222.
Garg, S.K., Maurer, H., Reed, K. and Selagamsetty, R., 2014. Diabetes and cancer: two
diseases with obesity as a common risk factor. Diabetes, Obesity and Metabolism, 16(2),
pp.97-110.
Guerrero, R.T.L., Chong, M., Novotny, R., Wilkens, L.R., Badowski, G., Blas-Laguana, M.
and Murphy, S., 2015. Relative validity and reliability of a quantitative food frequency
questionnaire for adults in Guam. Food & nutrition research, 59(1), p.26276.
Hemming, K., Haines, T.P., Chilton, P.J., Girling, A.J. and Lilford, R.J., 2015. The stepped
wedge cluster randomised trial: rationale, design, analysis, and reporting. Bmj, 350, p.h391.
Jaacks, L.M., Siegel, K.R., Gujral, U.P. and Narayan, K.V., 2016. Type 2 diabetes: a 21st
century epidemic. Best Practice & Research Clinical Endocrinology & Metabolism, 30(3),
pp.331-343.
James, S., Rao, S.V. and Granger, C.B., 2015. Registry-based randomized clinical trials—a
new clinical trial paradigm. Nature Reviews Cardiology, 12(5), p.312.

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Opie, C., 2019. Research approaches. Getting Started in Your Educational Research: Design,
Data Production and Analysis, p.137.
Teare, M.D., Dimairo, M., Shephard, N., Hayman, A., Whitehead, A. and Walters, S.J., 2014.
Sample size requirements to estimate key design parameters from external pilot randomised
controlled trials: a simulation study. Trials, 15(1), p.264.
Teare, M.D., Dimairo, M., Shephard, N., Hayman, A., Whitehead, A. and Walters, S.J., 2014.
Sample size requirements to estimate key design parameters from external pilot randomised
controlled trials: a simulation study. Trials, 15(1), p.264.
Tobias, D.K., Pan, A., Jackson, C.L., O'reilly, E.J., Ding, E.L., Willett, W.C., Manson, J.E.
and Hu, F.B., 2014. Body-mass index and mortality among adults with incident type 2
diabetes. New England Journal of Medicine, 370(3), pp.233-244.
Williams, P.T. and Thompson, P.D., 2014, September. Increased cardiovascular disease
mortality associated with excessive exercise in heart attack survivors. In Mayo Clinic
Proceedings (Vol. 89, No. 9, pp. 1187-1194). Elsevier.

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