Effect of Aerobic and Arm Exercises on HbA1c and Immunological Properties of Breast Milk in Diabetic Lactating Women

Journal of Environmental Treatment Techniques

2020, Volume 8, Issue 4, Pages: 1420-1424

J. Environ. Treat. Tech.

ISSN: 2309-1185

Journal web link: http://www.jett.dormaj.com

https://doi.org/10.47277/JETT/8(4)1424

Effect of Aerobic and Arm Exercises on HbA1c and

Immunological Properties of Breast Milk in

Diabetic Lactating Women

Magda Sayed Morsi *, Adel Farouk El Begawy , Reham Hamed Saad Hamza

Department of Physical Therapy for Woman’s Health, Faculty of Physical Therapy, Cairo University, Egypt

Department of Gynecology and Obstetrics, Faculty of Medicine, Cairo University, Egypt

Abstract

Objective: To assess the therapeutic efficacy of aerobic and arm exercises on glycated hemoglobin (HbA1c) and immunological

properties of breast milk in diabetic lactating women. Material and Methods: This study was carried out on thirty breast feeding

diabetic lactating women. They were randomly divided into two groups. Group (A) received aerobic and arm exercises, diet program

and medications for 8 weeks (n=15), while group (B) received diet program and medications for 8 weeks (n=15). HbA1c and

immunological properties of breast milk (IgA, lactoferrin and lysozyme) were evaluated before and after treatment for both groups.

Results: Comparing both groups post-treatment showed that there were a statistically significant reduction in HbA1c (p<0.05) and

statistically significant increases in all immunological properties of breast milk (p<0.05) in favor of group (A). Conclusion: Aerobic

and arm exercises have a significant positive effect on HbA1c and immunological properties of breast milk in diabetic lactating

women.

Keywords: Diabetic lactating women, Aerobic and arm exercises, HbA1c, Breast milk, Immunological properties

Introduction¹

synthesis and secretion of immunoglobulins [3]. Hence,

physical therapy programs for improving glycemic control

and breast milk immunological properties in diabetic lactating

women are desirable.

Lactation gives immunological support for the infant

against infections during the first months of life and over the

long-term. Accordingly, the American Academy of Pediatrics

reaffirms its recommendation of exclusive breast feeding for

six months followed by continued breast feeding with

introducing complementary foods for at least one year [1].

Immunoglobulin A (IgA), lactoferrin and lysozyme represent

three proteins that are found in relatively high levels in breast

milk and provide beneficial immunological impact. IgA

prevents bacterial adherence to mucosal surfaces and

neutralizes toxins from microorganisms. Lactoferrin works at

the mucosal sites and has antimicrobial and anti-inflammatory

activities. It competes with bacteria for ferric iron and

prevents the growth of microorganisms. Lysozyme is a

protein that provides bacterial lysis and works synergistically

with IgA and lactoferrin in antibacterial functions [2].

Diabetic lactating women have decreased concentrations of

immunological factors in their breast milk. The total IgA

concentration in diabetic breast milk was 63.6% lower than in

those without gestational diabetes [3]. The reduced

immunoglobulins in breast milk of diabetic women could be a

result of reduced function of B-cell lymphocyte associated

with hyperglycemia in diabetes [4-6]. Another mechanism

explaining the reduction in milk immunoglobulins in diabetic

women could stem from the reduced circulating levels of

prolactin associated with obesity and diabetes as demonstrated

in insulin-dependent diabetes mellitus [7]. Prolactin regulates

humoral immunity by binding to prolactin receptors on B

lymphocytes and stimulating ornithine decarboxylase, the

rate-limiting enzyme in polyamine biosynthesis required for

Regular exercise is a cornerstone of treatment for

diabetes. In the 2018 Diabetes Standards of Care publication,

the American Diabetes Association recommended most

patients with diabetes should engage in 150ꢀminutes or more

of moderate intensity physical activity per week [8]. Aerobic

exercise increases work capacity, improves cardio respiratory

fitness, improves insulin sensitivity, improves glycemic

control as reflected in HbA1c, enhances the immune function

and brings favourable changes in body mass, body

composition and lipid profile, even without dietary restriction

[

9-11]. Previous studies investigated the effect of maternal

exercise on immunological properties of breast milk in

healthy lactating women [2, 12]. Additionally, other studies

examined the effect of exercise training on glycemic control

in diabetic patients [13, 14]. However, none of them had

examined the effect of maternal exercise on glycemic control

and immunological properties of breast milk in diabetic

lactating women. Therefore, this study was the first one which

aimed to investigate the effect of aerobic and arm exercises on

HbA1c and immunological properties of breast milk in

diabetic lactating women.

2 Materials and methods

2.1 Study Design

The study was designed as a prospective, pre- and post-

test, randomized, controlled trial. Ethical approval was

obtained from the institutional review board at Faculty of

Physical Therapy, Cairo University. The study followed the

Guidelines of Declaration of Helsinki on the conduct of

human research. It was conducted between May 2019 and

February 2020.

Corresponding author: Magda Sayed Morsi, Department of

Physical Therapy for Woman’s Health, Faculty of Physical Therapy,

Cairo University, Egypt. E-mail: rehamhmed@gmail.com

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2020, Volume 8, Issue 4, Pages: 1420-1424

.2 Participants

Thirty sedentary, nonsmoking, diabetic lactating women

2.5 Outcome Measures

were selected, from the Outpatient Clinic of Gynecology and

Obstetrics, Imbaba General Hospital and Kasr Al- Ainy

Hospital, to engage in this study. They had delivered a single,

full-term, healthy infant without any complications. Their

HbA1c was greater than or equal to 6.5%, their ages ranged

from 25 to 35 years old and their body mass index (BMI)

2.5.1 Plasma blood HbA1c

Blood samples were collected from all diabetic lactating

women in both groups to measure plasma levels of HbA1c, a

weighted average of blood glucose levels during the preceding

120 days [17], pre- and post-treatment. Samples were

collected into serum separating tubes and allowed to clot at

room temperature for 30 minutes. Then, centrifugation of

blood clot was done at 3000 g for 15 minutes. Aliquots of the

serum samples were stored at −20 °C for further use. HbA1c

was measured by using high performance Elisa kit (Bionic

Company, China) [18].

ranged from 25 to 30 Kg/m . Lactating women were excluded

if they had poor lactation, nipple problems (retracted, cracked,

inflamed or inverted nipples), breast cancer, previous

surgeries in breast or chest, any cardiorespiratory disease,

anemia, immune dysfunction, infectious diseases or

psychiatric disorders. Additionally, lactating women that had

received contraceptive pills or corticosteroid medications

were excluded from this study.

2.5.2 Analyses of immunological properties of breast milk

A sample of 10 mL of breast milk was collected from

each diabetic lactating woman in both groups to check the

concentrations of IgA, lactoferrin and lysozyme pre- and post-

treatment. Samples were collected into sterile sample bottles

and transported on ice to the laboratory for analysis through

an enzyme-linked immunosorbent assay procedure. IgA was

analyzed by Human IgA ELISA core kit (KOMA BIOTECH),

while both lactoferrin and lysozyme were analyzed by

AssayMax Human ELISA kit (ASSAYPRO, USA) [19].

.3 Randomization

Informed consent was obtained from all participants

following the detailed explanation of the study. The privacy of

all received data and the right to refuse or leave at any

moment were also provided to all participants. The diabetic

lactating women were randomly assigned into two groups (A

and B) using a computer-generated randomization cards saved

in sealed envelopes. After randomization, there was no

dropping out of subjects.

2.6 Statistical analysis

Statistical Package for Social Science (SPSS) computer

program (version 23 windows) was used for data analysis.

Results were expressed as mean and standard deviation (SD).

The Kolmogorov–Smirnov distribution test was used for

examining normal distribution of data. In comparing

quantitative data, the unpaired samples t-test was used in

intergroup comparison of parameters, while the Paired

samples t-test was used for intragroup comparisons. The level

of significance was set at P value of less than or equal to 0.05.

.4 Interventions

Group (A) included 15 diabetic lactating women who

received aerobic and arm exercises plus diet program for 8

weeks, while group (B) included 15 diabetic lactating women

who received medications plus diet program for 8 weeks.

.4.1 Aerobic and arm exercises

Each diabetic lactating woman in group (A) received

aerobic exercise for 30 minutes using treadmill and received

arm exercise for 15 minutes using multi gym machine for 8

weeks. For aerobic exercise performance, participants were

asked to walk on treadmill for 30 minutes (five minutes of

warm up, 20 minutes of moderate aerobic exercise at 60 to

Results

Both groups were similar at baseline (P>0.05) regarding

age, weight, height, BMI and all outcome measures (tables 1-

). The HbA1c showed a statistically significant reduction

0% of maximal heart rate (HRmax) and 5 minutes of cooling

down). HRmax was calculated by subtracting the age from

20 [15]. Then, participants were asked to perform arm

within both groups (A and B) (P<0.05). Also, the post-

treatment comparison of both groups revealed a statistically

significant reduction in HbA1c (P<0.05) in favour of group

exercise for 15 minutes using multi gym machine to train

upper limb muscles including chest and arms muscles. The

duration of the treatment session was 45 minutes, 3 times per

week, for 8 weeks.

(

A) (Table 2). The immunological properties of breast milk

IgA, lactoferrin and lysozyme) showed statistically

significant increases within both groups (A and B) (P<0.05).

Also, the post-treatment comparison of both groups revealed a

statistically significant increases in all immunological

properties of breast milk (P<0.05) in favour of group (A)

.4.2 Diet program

All diabetic lactating women in both groups (A and B)

(Table 2).

received diet program to follow it during treatment course.

They were instructed to eat every day 2-3 servings of protein

foods (e.g. meat, poultry, fish, eggs, beans, nuts and seeds), 4-

Discussion

Diabetic lactating women have higher levels of HbA1c in

servings of dairy products (e.g. milk and yoghurt), 2-4

their blood and lower levels of immunological factors in their

breast milk [3, 20]. Therefore, the present study aimed to

investigate the effect of aerobic and arm exercises on HbA1c

and immunological properties of breast milk in diabetic

lactating women. The results of the present study revealed that

there were a statistically significant reduction in HbA1c and

statistically significant increases in all immunological

properties of breast milk (IgA, lactoferrin and lysozyme) post-

treatment in favor of group (A). These results indicated the

effectiveness of aerobic and arm exercises in improving

glycemic control and immunological properties of breast milk

in diabetic lactating women.

servings of vegetables per day (including dark green and

yellow vegetables), 2-3 servings of fruit per day, and 4-5

servings of whole grains (e.g. whole wheat breads, pasta,

cereal and oatmeal), as well as drink plenty of water (6-8

glasses) and fluids daily [16].

.4.3 Medications

All diabetic lactating women in both groups (A and B)

were instructed to follow medications prescribed by physician

for diabetes during treatment course.

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2020, Volume 8, Issue 4, Pages: 1420-1424

Table 1: Demographic features of women in both groups

Group (A)

n = 15)

Group (B)

(n = 15)

Characteristics

P value

(

Age (years)

Weight (Kg)

Height (cm)

29.93 ± 2.46

71.27 ± 3.39

159.33 ± 3.90

28.06 ± 0.76

29.47 ± 3.07

73.27 ± 3.31

160.40 ± 3.91

28.47 ± 0.67

0.649 ^N^S

0.113 ^N^S

0.461 ^N^S

0.131 ^N^S

BMI (Kg/m²)

P > 0.05 = non-significant, P = Probability.

Table 2: HbA1c and immunological properties of breast milk for both groups

Group (A)

n = 15)

Group (B)

(n = 15)

P value*

(

HbA1c (%)

Pre-treatment

Post-treatment

P value**

7.33 ± 0.67

6.43 ± 0.50

7.37 ± 0.55

6.90 ± 0.51

0.883

0.017

0.001

IgA (μg/ml)

Pre-treatment

Post-treatment

P value**

174.43 ± 13.70

240.06 ± 18.02

180.61 ± 7.40

220.69 ± 22.82

0.139

0.015

0.001

Lactoferrin (μg/ml)

Lysozyme (μg/ml)

Pre-treatment

Post-treatment

P value**

Pre-treatment

Post-treatment

837.93 ± 66.65

912.62 ± 71.77

813.98 ± 59.12

850.05 ± 64.56

0.307

0.018

0.001

272.90 ± 49.00

354.07 ± 41.65

268.55 ± 32.36

317.95 ± 37.90

0.777

0.019

P value**

0.001 ^S

Inter-group comparison; ** intra-group comparison of the results pre- and post-treatment.

P > 0.05 = non-significant, P < 0.05 = significant, P = Probability.

Regarding HbA1c in group (A), our result was in line with

previous studies that reported the positive effect of aerobic

exercise on reducing HbA1c levels in diabetic subjects [21-

concluded that structured nutrition therapy alone improves

HbA1c in overweight and obese diabetics. Regarding

immunological properties of breast milk in group (A), the

results of this study came in line with Cieslak et al. [28] who

reported that moderate exercise has a positive effect on the

immune system through enhancing cell-mediated immunity

and increasing IgA. Each session represents a boost in

immune surveillance [29]. The mechanisms by which the

moderate aerobic exercise caused significant increases in all

immunological properties of breast milk (IgA, lactoferrin and

lysozyme) are still unknown. However, the results of this

study could be supported with Osman et al. [1] who found that

moderate aerobic exercise produced a significant increase in

breast milk lymphocytes. Since decreased B-cell lymphocyte

function associated with hyperglycemia in diabetics causes

decreased immunoglobulins in their breast milk [4-6], the

improvement in lymphocytes associated with moderate

aerobic exercise could result in increased immunoglobulins

levels in diabetic breast milk. Additionally, prolactin plays a

role in regulating humoral immunity [3]. Therefore, the

significant increase in immunological properties of breast

milk might be a result of the significant increase of plasma

prolactin concentrations in exercising mothers that previous

studies had demonstrated [30,31]. This increase of plasma

prolactin might be in turn resulted in increase of breast milk

prolactin which correlates significantly with total protein in

milk [32]. In contrast, the results of the present study

disagreed with Lovelady et al. [2] who reported that lactating

mothers who exercised aerobically at least 30 minutes/day for

3 days/week had no significant differences in breast milk

concentrations of IgA, lactoferrin and lysozyme. Also, Groër

and Shelton [12] found that IgA concentrations in breast milk

4]. On the other hand, Aggarwala et al. [25] found non-

significant changes in HbA1c following aerobic training. The

contrast between studies could be related to the differences in

different exercise parameters. The significant improvement in

HbA1c reported in group (A) in the present study could be

explained by the improving effect of physical training on

insulin action primarily in skeletal muscle. The mechanism

behind this effect involves a number of adaptations like

increased capillary density and GLUT 4 content, a shift

towards more insulin sensitive fiber types, alterations in the

sarcolema phospholipids composition, increased activity of

glycolytic and oxidative enzymes and increased activity of

glycogen synthase. Exercise causes glucose uptake increase in

skeletal muscle in addition to 5’AMP- activated protein kinase

activity increase, resulting in enhancement of glucose

transport through increased cell surface GLUT 4 content in

insulin resistant skeletal muscle and mediation of the effects

of GLUT4 expression [21]. Moreover, regional adiposity,

especially visceral and intramuscular fat stores, has a direct

relationship to insulin insensitivity via fat-specific cytokine-

mediated pathways. There is also

a direct impact of

intramyocellular fat storage on insulin receptor function

within muscle tissue. Therefore, reduced fat mass through

exercising diminishes the adverse effect of these factors [26].

Regarding HbA1c in group (B), the reported significant

improvement was consistent with Sami et al. [17] who

revealed that dietary management is a superior option for

keeping HbA1c levels in an acceptable range and achieving

glycemic control in diabetic patients. Also, Mottalib et al. [27]

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2020, Volume 8, Issue 4, Pages: 1420-1424

were not affected by maternal exercise in 4-6 weeks

postpartum women. However, significant limitations of those

two previous studies are the cross-sectional design and use of

self-reported exercise. The significant improvement in

immunological properties of breast milk in group (B) could be

related to the effect of maternal nutritional status. Chang [33]

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milk of well-nourished women were twice their

concentrations in malnourished women during the first 7 days

of lactation and at most stages up to 8 weeks thereafter.

These results provide new data about the therapeutic efficacy

of aerobic and arm exercises on HbA1c and immunological

properties of breast milk in diabetic lactating women. Further

studies are needed in order to clarify the mechanisms

underlying these responses to aerobic and arm exercises.

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Conclusion

Aerobic and arm exercises for 8 weeks are effective in

081.

improving glycemic control and increasing immunological

properties of breast milk in diabetic lactating women.

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Acknowledgments

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The authors would like to thank all individuals who

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All authors of this study have a complete contribution for

data collection, data analyses and manuscript writing.

Funding

Not funded.

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