Effect of Moderate Intensity Aerobic Exercise on Fertility Hormones in Male Obese Individual in Nnewi, Nigeria

Ifeoma Joy Onuora; Samuel Chukwuemeka Meludu; Chudi Emmanuel Dioka; Chikaodili Nwando Obi-Ezeani

doi:10.4103/jihs.jihs_22_21

ORIGINAL ARTICLE

Year : 2022 | Volume : 10 | Issue : 1 | Page : 3-7

Effect of Moderate Intensity Aerobic Exercise on Fertility Hormones in Male Obese Individual in Nnewi, Nigeria

Ifeoma Joy Onuora¹, Samuel Chukwuemeka Meludu², Chudi Emmanuel Dioka¹, Chikaodili Nwando Obi-Ezeani¹
¹ Department of Chemical Pathology, Nnamdi Azikiwe University, Awka, Anambra, Nigeria
² Department of Human Biochemistry, Nnamdi Azikiwe University, Awka, Anambra, Nigeria

Date of Submission	14-Aug-2021
Date of Decision	16-Jan-2022
Date of Acceptance	22-Jan-2022
Date of Web Publication	22-Aug-2022

Correspondence Address:
Dr. Ifeoma Joy Onuora
Department of Chemical Pathology, Nnamdi Azikiwe University, Awka, Anambra
Nigeria

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jihs.jihs_22_21

Abstract

Context: Obesity is a major global public health issue which could result from sedentary lifestyle and poor dieting, and consequently hormonal imbalance. Aim: To evaluate fertility hormones in male obese subjects, and the subsequent effect of moderate intensity aerobic exercise on these parameters after 12 weeks of intervention. Subjects and Methods: 90 obese (48 class I and 42 class II) and 50 normal weight (control) subjects were recruited. Subsequently, 18 male obese subjects were randomly selected and subjected to a 12-week aerobic training program using a total cross bar machine, three sessions weekly, which consisted of a 10–15 min warm-up and 35–50 min total cross bar machine exercise. Blood samples were collected at baseline, 6 weeks and after 12 weeks of intervention for luteinizing hormone, follicular stimulating hormone (FSH), prolactin, testosterone, and estradiol using enzyme-linked immunoassay. Statistical Analysis: Statistics was done using SPSS version 23. Results: The mean level of testosterone and FSH was significantly lower while estradiol was significantly higher in class I and II when compared with the control (P < 0.05). On subjecting them to 12 weeks exercise, there were significant increases in FSH and testosterone and decrease in estradiol when compared with the baseline values (P < 0.05). Conclusion: Weight loss through moderate intensity exercise may improve the reproductive hormone profile of male obese individuals, thereby reducing rate of infertility.

Keywords: Estradiol, exercise, follicle-stimulating hormone, obesity, prolactin, testosterone

How to cite this article:
Onuora IJ, Meludu SC, Dioka CE, Obi-Ezeani CN. Effect of Moderate Intensity Aerobic Exercise on Fertility Hormones in Male Obese Individual in Nnewi, Nigeria. J Integr Health Sci 2022;10:3-7

How to cite this URL:
Onuora IJ, Meludu SC, Dioka CE, Obi-Ezeani CN. Effect of Moderate Intensity Aerobic Exercise on Fertility Hormones in Male Obese Individual in Nnewi, Nigeria. J Integr Health Sci [serial online] 2022 [cited 2023 Jun 10];10:3-7. Available from: https://www.jihs.in/text.asp?2022/10/1/3/354228

Introduction

The global increase in prevalence of overweight and obesity has resulted in calls for prevention and treatment strategies. Obesity and physical inactivity may be associated with erectile dysfunction and hypogonadism.^[1] It has been suggested that moderate regular exercise has a positive impact on fertility and assisted reproductive technology outcomes,^[2],[3],[4] and hormones are specific regulatory molecules that control reproduction.^[5],[6],[7] There have been conflicting findings on the effect of moderate-intensity exercise on male fertility hormones, therefore this study aims at evaluating fertility hormones in male obese subjects residing in Nnewi, and the subsequent effect of moderate-intensity aerobic exercise on these fertility hormones.

Subjects and Methods

Study participants and study area

The participants consisted of obese and normal weight male individuals between the ages of 29 and 47yrs residing in Nnewi town. The research was carried out at Nnewichi and Akaboezem in Nnewi town, Anambra state, Nigeria. Biochemical analysis was carried out at Nnamdi Azikiwe Teaching Hospital (NAUTH), Nnewi. The Gymnasium center used for exercise was “The Nnewi Hotel and Event Centers located in Akaboezem, Nnewi.

Sample size

Sample size was determined using a statistical method for comparing groups when population is more than 10000. The prevalence rate of obese male individual according to Akarolo-Anthony et al.,^[8] is 3%.

The formula is as follows: (Daniel, 2013)^[9]

Where;

N = Minimum sample size;

Z = 95% confidence interval given at 1.96;

p = Proportion of the population estimated to have the public health problem under study

(Prevalence rate of obesity) in percentage (%) of factor under consideration = 3.0%.^[8]

q = Complimentary probability of q = 1 − p

d = Degree of accuracy or precision level = 0.05

N = 3.84 × 0.03 (1-0.03)

0.0025

Sample size (N) = 45.5

10% of attrition is 4.5, therefore N = 50

Sampling technique

Convenience sampling technique was used to enroll participants. The selection was done based on participants who gave written informed consent after discussing the design of the study with them.

Study design

This involves a cross-sectional and an interventional study. The cross-sectional study involved 90 male obese subjects made up of 48 class I and 42 class II obesity and 50 normal weight control subjects. The interventional study involved 18 male obese subjects who were randomly selected and subjected to moderate-intensity exercise using Total-Body Cross Bar machine. The maximum heart rate is recognized as 220 minus the age (in years) of the person, and heart rate monitors were used to control participants' training intensity.

Methods used to achieve moderate intensity exercise

Met calories = 3–5.9 calories
% Maximum heart rate (% HRmax) = 64%–76%
Rating of perceived exertion (Borgs scale score = 12–13 (breathing is faster but compatible with speaking full sentence).

Inclusion and exclusion criteria

Apparently, healthy individuals aged between 29 and 47 years with body mass index (BMI) of 30–34.9 kg/m² (class I obese), 35–39.9 kg/m² (class II obese), and 19–24.9 kg/m² for nonobese (controls) were included in the study. However, subjects taking alcohol or cigarette, with BMI above 41 kg/m² (morbid obesity), the incapacitated, physically challenged, and physically active were excluded from the study.

Ethical consideration

The ethical approval for this study was obtained from the Research Ethics Committee, Nnamdi Azikiwe University Teaching hospital Nnewi, Anambra state with reference NAUTH/CS/66/VOL10/2018/010.

Data collection

Subjects who gave their written informed consent, following discussions at different areas including business centers, churches, restaurants, and offices were given questionnaires to fill. It contains information about the subject's demographic data, anthropometric measurements, biochemical details, and clinical parameters (lifestyle and dietary habits, medical and family history).

Anthropometric measurements

The body weights of the participants were measured in kilograms (kg) using a weighing scale (Gulfex Medical and Scientific, England) and recorded to the nearest 0.1 kg. Heights were measured in meters using a height scale calibrated in centimeters, and the reading was also taken to the nearest 0.1 cm. Generalized obesity was determined in each adult participant from the BMI value which was calculated by dividing the weight in kilograms by the square of the height in meters (kg/m²). Abdominal obesity was determined by measuring the waist circumference (WC) of the participants, and this was measured using a stretch-resistant tape (HTS, China).

Sample collection and biochemical analysis

Five milliliters of blood was collected from each participant between 8 am and 10 am before exercise (baseline), 6 weeks and 12 weeks after exercise according to standard procedure. The blood sample was dispensed into plain tubes, allowed to retract and then spun at 3000 revolutions per minute for 10 min. The serum obtained was used for used for analyses of luteinizing hormone (LH), follicular stimulating hormone (FSH), testosterone, estradiol, and prolactin based on solid phase enzyme-linked immunosorbent assay method using Mindray (MR-96A).

Statistical analysis

This was performed using Statistical Package for Social Sciences (SPSS Inc. Chicago, IL, USA) version 23.0. Variables were expressed as mean ± standard deviation after subjecting to them to normality test and found to be normally distributed. Analysis of variance and post hoc was used to compare the differences among Class I obese, Class II obese, and nonobese (control) groups and inter-group variability, respectively. Paired t-test was used to assess the mean difference between two related variables, and the level of significance was set at P < 0.05.

Results

The mean serum levels of testosterone and FSH were significantly lower whereas estradiol was significantly higher in Class II and I obese when compared with the control (P < 0.05). There were no significant differences in mean levels of LH and prolactin in the obese groups when compared with the control group (P > 0.05) neither were there any significant differences in the levels of the fertility hormones in Class II obese when compared with Class I obese (P > 0.05) as shown in [Table 1].

Table 1: Mean levels of fertility hormones in class II Obese, class I obese and control groups

Click here to view

On subjecting the obese male subjects to exercise, significant weight loss was observed after 6-weeks and 12-weeks when compared with the baseline but there was no reduction in WC after 12-weeks of exercise when compared with baseline as shown in [Table 2].

Table 2: Mean values of weight and waist circumference at different stages of exercise

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In [Table 3], there were significant increases in FSH and testosterone levels and decrease in estradiol level after exercising for 12-weeks when compared with the value at baseline (P < 0.05).

Table 3: Mean levels of fertility hormones at different stages of exercise

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Discussion

Hormonal changes are more likely to result from abdominal or visceral fat than fat stored in other parts of the body. Spermatogenesis continuously takes place in men as part of the reproductive function, and this process is influenced by LH and FSH which are secreted by the anterior lobe of the pituitary. LH stimulates testosterone release and acts with FSH to initiate sperm production and its maintenance.^[10],[11] This study showed a significant reduction in testosterone and FSH levels with increased estradiol level in class II obese subjects when compared with the normal weight individuals. This may be due to the elevated white adipose tissue in obese men which in turn exhibits high aromatase activity and also secretes adipose-derived hormones and adipokines, thus presenting high estrogen as well as low testosterone and FSH levels. This excess estrogen maybe linked to overactivity of the aromatase cytochrome P450 enzyme. This enzyme is responsible for a key step in the estrogens biosynthesis, and the expression level is high in white adipose tissue.^[12] Hypogonadism or androgen deficiency present in obese males or those with metabolic syndrome may contribute to problems with spermatogenesis and erectile dysfunction. In addition, many other obesity-associated hormones may as well alter the male reproductive function. Reduced spermatogenesis associated with severe hypotestosteronemia in morbidly obese individuals may add to infertility.^[13] Visceral obesity may serve as a major endocrine disruptor and also influence the endocrine interactions by reducing LH and testosterone levels, and consequently hypogonadotropic hypogonadism which is a condition that contributes to infertility in males. Increased body weight or weight gain are often associated with prolactinomas irrespective of a mass effect on the hypothalamus or pituitary function. Weight gain is mostly associated with prolactinomas which produce high levels of prolactin.^[14] A previous study on obese women showed that increased BMI is associated with an increased secretion rate of prolactin.^[15] The prolactin level in obese subjects did not differ significantly from the normal weight group, and this finding is in agreement with a previous community-based study which showed no association between BMI and prolactin in both men and women.^[15] Exercise has been shown to be a stress factor capable of altering the levels of some hormones and enzymes in the body.^[16] Moderate physical activity may enhance health as well as quality of life, however, excessive or exhaustive exercises can have undesirable outcomes, the most recently recognized being possible fertility problems in both males and females. The present study examined the reproductive profiles of male obese subjects who exercised regularly (moderate intensity) for 12 weeks. From this study, it was observed that subjecting obese individuals to moderate intensity exercise showed significant weight loss after 6 and 12 weeks with no significant reduction in WC after 12 weeks. This corresponds with the report of Maiya et al.^[17]

There were significant increases in FSH and testosterone and decrease in estradiol after exercising for 12 weeks. This agrees with the work done by Khoo et al.,^[18] Ari et al.,^[19] and McTiernan et al.^[20] A previous study which investigated the effect of 6 months period of physical exercise on plasma testosterone and LH levels found that these hormone levels increased by 21% and 25%, respectively, which agrees with this present study.^[11] Furthermore, LH and prolactin though increased and decreased, respectively, after 6 and 12 weeks exercise did not show any significant difference. However, Yıldırım and Muhammed^[21] observed significant reduction in estradiol level in exercising group but no difference in testosterone and FSH. In contrast to this work, Vaamonde et al.^[22] have shown that maximal intensity exercise enforced on physically active individuals during a short period of time results in changes in FSH, LH and prolactin with no significant changes in testosterone and estradiol. The reduction in circulating estrogens by reducing adiposity through exercise was as a result of reduced conversion of androgens to estrogens by the aromatase enzyme. In addition to change in adiposity, exercise may also have other effects including a reduction in insulin levels, and consequently increases sex hormone binding globulin levels and decreases bioavailability of estradiol.^[21] Safarinejad et al.^[23],[24] had reported that long-term strenuous treadmill exercises adversely affect reproduction. The serum LH and FSH levels were reduced after 12 weeks of exercise. The beneficial or detrimental effects of physical activity or exercise are dependent on the several inherent exercise schedule factors including intensity, type, and volume. Both the volume of training and the intensity of exercise induce or influence hormonal profile as well as hormonal alterations.

Conclusion

From this study, obesity has been found to cause alterations in male sex hormonal profile, however, exercise may have potentials of reversing these effects. Weight management is essential in preventing infertility, and moderate-intensity aerobic exercise is an important aspect of weight management which positively influences fertility and promotes a myriad of health benefits independent of weight loss.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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