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The effect of aerobic exercise on serum ferritin levels in untrained middle-aged women

Authors:

Abstract

Background: Recent studies suggest that an elevated serum ferritin concentration is considered a dependent factor associated with increased risk cardiovascular disease. The aim of this research is finding of the effect of six months aerobic exercise on serum ferritin levels in untrained middle-aged women. Methods: Nineteen healthy female middle-aged were selected by convenience sampling method and were randomly divided into two experimental (n=11) and control (n=8) groups. The exercise protocol included aerobic exercise training lasted for 6 months and 3 sessions per week and every session lasted for 60 minutes and with intensity of 55-65 percent of maximum heart rate reserve (MHR). Blood samples were taken to measure serum ferritin before and after aerobic training period. General linear-Repeated measures (GL-RM) was used to comparing of within, Interactive and between means groups. The level of significance was set at P< 0.05. Results: Weight, BMI, body far percent, WHR in exercise group towards the end of period of the training, but this changes was not significantly. Results showed a variance between group WHR is significant (P<0.05). In addition, during the training, there was no significant change in serum Ferritin levels in both groups. Conclusion: Six months of aerobic exercise does not induce significant change in serum levels of Ferritin, while these levels reduced in middle-aged women. We believe that prolong exercise, due to reduce in serum ferritin. Although more research, as well as basic research and large-scale epidemiological studies, is required to totally assess the association between Ferritin concentrations and prolong exercise.
379
International Journal of Sport Studies, Vol., 2 (8), 379-384, 2012
Available online at http://www.ijssjournal.com
ISSN 2251-7502 ©2012 VictorQuest Publications
The effect of aerobic exercise on serum ferritin levels in untrained
middle-aged women
Nahid Bijeh (PhD)
1
, Keyvan Hejazi (Msc)
2*
1- Faculty of Physical Education and Sport Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
2- Department of Physical Education and Sports Sciences, Ferdowsi University of Mashhad,
Mashhad, Iran
*Corresponding author, Email: Keyvanhejazi@yahoo.com
Abstract
Background: Recent studies suggest that an elevated serum ferritin concentration is considered a
dependent factor associated with increased risk cardiovascular disease. The aim of this research is
finding of the effect of six months aerobic exercise on serum ferritin levels in untrained middle-aged
women.
Methods: Nineteen healthy female middle-aged were selected by convenience sampling method and
were randomly divided into two experimental (n=11) and control (n=8) groups. The exercise protocol
included aerobic exercise training lasted for 6 months and 3 sessions per week and every session lasted
for 60 minutes and with intensity of 55-65 percent of maximum heart rate reserve (MHR). Blood samples
were taken to measure serum ferritin before and after aerobic training period. General linear- Repeated
measures (GL-RM) was used to comparing of within, Interactive and between means groups. The level of
significance was set at P< 0.05.
Results: Weight, BMI, body far percent, WHR in exercise group towards the end of period of the training,
but this changes was not significantly. Results showed a variance between group WHR is significant
(P<0.05). In addition, during the training, there was no significant change in serum Ferritin levels in both
groups.
Conclusion: Six months of aerobic exercise does not induce significant change in serum levels of Ferritin,
while these levels reduced in middle-aged women. We believe that prolong exercise, due to reduce in
serum ferritin. Although more research, as well as basic research and large-scale epidemiological studies,
is required to totally assess the association between Ferritin concentrations and prolong exercise.
Keywords: Ferritin, Physical activity, untrained middle-aged women
Introduction
Many epidemiologic studies reported over the past 50 years have confirmed nearly consistently an
association of elevated blood serum ferritin level with cardiovascular disease, though not all have found
that the relation is independent of other risk factors (Manfroi et al., 1999). Ferritin is an iron-phosphorus-
protein complex that is an index of body iron stores. Iron is very important for oxygen transportation to
tissues and major functions in cellular oxidation mechanisms (Dorland, 1994). Elevated serum iron leads
to increased serum ferritin concentration (Jehn et al., 2007; Yamanishi et al., 2007).
Ferritin level serves as a biomarker for evaluating body iron contents. Tissue and organ damage happens
once iron concentrations are elevated (Ikeda et al., 2006) because increased iron accumulation or serum
ferritin concentration may be a cause for the risk of heart attack (Rasmussen et al., 2001). Hence,
380
according to the epidemiologic research on this hypothesis may be divided into studies of the association
of CHD risk with 1) blood serum ferritin; 2) other measures of body iron stores, less correct than blood
serum ferritin, eg, heterozygous hemochromatosis; blood donation and transferring saturation (Sempos,
2002). Studies reported in literature on the effect of exercise on serum ferritin have been conflicting and
inconsistent.
Recent studies reported that physical activities play an important role in reducing serum ferritin
concentration (Furqan et al., 2007; Liu, et al., 2003). An increase in physical activity decreased serum
ferritin concentration (Furqan et al., 2007), and a decrease in serum ferritin concentration was shown to
depend on duration and frequency of physical activity (Lakka et al., 1994). Naimark et al., (1996) found a
similar pattern for performance and ferritin concentration. The mean serum ferritin reduced considerably
once twenty four weeks in those who walked five days for each week, but not in those who walked three
days per week. Furqan at al., (2007), reported moderate physical activity to be more important in lowering
serum ferritin than vigorous activity. Bartfay et al., (1995), Demonstrated regular exercise could decrease
serum ferritin concentrations. Lakka and colleagues, (1994) reported mean ferritin concentration to be
16.8% lower in individuals with the highest quartile of physical activity as compared to those with the
lowest duration of activity, and to be 19.9% lower in individuals with the highest category of physical
activity frequency (>3 sessions per week) as compared to those with the lowest activity frequency (<1
session per week). Salonen et al., (1992) were the first to report a significant association between serum
ferritin concentrations and risk of heart attack. They found that Finnish men with a serum ferritin
concentration 200 µg/L had an ≈2-fold higher risk of heart attack than did men with a concentration <
220 µg/L. They also reported finding a significant linear association between serum ferritin and risk of
heart attack. However, the majority of prospective epidemiologic research found no association between
serum ferritin (Manttari et al., 1994; Stampfer et al., 1993), or other measures of iron level (Baer et al.,
1994; Sempos et al., 1994), and CHD.
The conflicting results about the effects of exercise on serum ferritin in conducted studies along with the
lack of sufficient evidence in examining the effects of sports activities on serum ferritin levels and also the
better discovery of physiological conditions of individuals during the prolong activity have made
researchers conduct some comparison research on the effects of aerobic exercise on serum ferritin in
untrained middle-aged. Therefore, the aim of this prospective study was therefore to determine the effect
of six months aerobic exercise on serum ferritin levels in untrained middle-aged women.
Materials and Methods
Subjects
This study was semi-experimental. Furthermore, it plan was confirmed by Research Assembly of Physical
Education and Sport Sciences Faculty of Ferdowsi University of Mashhad. During first stage, the subjects
of this study were nineteen healthy and inactive female who randomly assigned into the experimental
(n=11) and control (n=8) groups. Before starting the program, written informed consents were taken from
all subjects. The levels of health and physical activity of the subjects were determined using general
practice physical activity questionnaire, physical activity readiness questionnaire and medical survey
(including electrocardiogram and blood pressure tests) by a specialist physician (Shephard, 1991). The
subjects were nonsmokers, received no drugs and had no metabolic disease and physical impairment
affecting their performance. During the second stage, their height was measured in centimeters using a
height determiner and their weight was calculated using a digital scale produced by a German company
called Beurer (PS07-PS06). The percent of body fat (PBF) was calculated using a body compound
determiner (model In-body-720 made in Korea) and based on a method called bioelectrical impedance.
All of these measurements were carried out while the volunteers had stopped eating or drinking 4 hours
prior to their test, and their bladder, stomach, and bowels were empty.
Exercise protocol
The exercise protocol included aerobic exercise training lasted for 6 months and 3 sessions per week and
every session lasted for 60 minutes and with intensity of 55-65 percent of maximum heart rate reserve
(MHRR). According to the MHRR for every single athlete was respectively calculated based on Karvonen
381
equation (1) and was also controlled during exercise by a heart rate monitor (made in Finland–Po-
lar)(Robbert & Landwehr, 2002).
Equation [1]: Target heart rate= [%60 or %70+ [(age-220) - (resting pulse]] + Resting heart rate
Blood sampling
During the study period, blood (about 2.5 ml) for determining whole blood indices and for biochemical
assays in serum was withdrawn from the antecubital vein in the morning (700-730) after overnight fasting
for 8 consecutive days, always after staying at least 15 min in sitting position.
Blood samples in all related studies were collected by venepunction from forearm vein after at least 15
minutes of sitting at rest or in the supine position. Blood sample were poured into a tube containing
K2EDTA and mixed for 15 min before analysis. After centrifuging samples in plastic capillary tubes using
Haemato Spin Centrifuge device.
The following assays were conducted in blood serum: ferritin concentration by using immunoenzymatic
commercial kits (BioSource, Belgium).
Statistical analysis
All statistical analyses were performed with SPSS version 15. The average and standard deviation of
data were calculated after checking the data distribution normalcy using Kolmogorov-Smirnov test and
Homogeneity of variance method. The comparison of between means groups and Homogeneity of groups
examined using Independent t-test. Repeated measure for comparison of variance within the group,
interaction (groups × phases) and between group was used. The level of significance was set at P< 0.05.
Results
According to the (Table 1), before the onset of the exercise, there were no significant differences between
groups in age, height and body composition variables including: weight, BMI, PBF and WHR. Also, there
were no significant differences between groups in the levels of Ferritin.
Tab
le
1
: Mean ± standard deviation and Indepen
dent t
-
test for
normality of two groups
Independent
t-test
M±SD* Group (s)
P-value
t
0.231 1.242
41.27±3.74 Exercise
Age (years) 43.25±2.91 Control
0.966 -0.044
155.36±5.48 Exercise
Height (cm) 155.25±5.77 Control
0.191 -1.34
64.85±5.83 Exercise
Weight (kg) 61.37±7.84 Control
0.232 -1.25
26.94±2.84 Exercise
BMI (kg/m2) 25.44±2.69
Control
0.706 -0.404
36.27±5.62 Exercise
PBF (%) 35.31±6.14 Control
0.281 -2.806
0.84±6.50 Exercise
WHR (cm) 0.76±6.64 Control
0.634 -0.485
32.18±6.11 Exercise
Ferritin
(ng/mL) 27.06±9.22 Control
A significant level P<0.05 *Data presented as mean ± standard
deviation
Intl. J. Sport Std. Vol., 2 (8), 379-384, 2012
382
Table
2
: Comparison of within group variance,
interaction and between group of body composition, se
-
rum Ferritin in Untrained Middle-Aged Women
Variations
Post-test
M±SD*
Pre-test
M±SD*
Group (s) Variables
Between groups Interaction
(group × phase)
Within groups
P-value
F
P-value
F
P-value
F
0.20 1.70 0.27 1.25 0.27 1.25
64.70±5.76 64.85±5.83 Exercise
Weight
(kg) 61.36±7.84 61.37±7.84 Control
0.32 0.99 0.06 20.1 0.44 0.59
26.43±2.58 26.94±2.84
Exercise
BMI
(kg/m
2
) 25.67±2.51 25.44±2.69 Control
0.76 0.09 0.00 9.72 0.82 0.05
36.02±5.54 36.27±5.62 Exercise
PBF (%) 35.52±6.20 35.31±6.14 Control
0.01
6.96 0.99 0.00 0.20 1.70
0.83±7.86 0.84±6.50 Exercise
WHR (Cm) 0.76±6.36 0.76±6.64 Control
0.109 2.86 0.634
0.23
5
0.158
2.18
0
28.82±4.64 32.18±6.13 Exercise
Ferritin
(mg/dL) 25.36±6.42 27.06±9.22 Control
A significant level P<0.05 *Data presented as mean ± standard deviation
According to the (Table 2), our results show decrease in weight, BMI, body far percent, WHR in exercise
group towards the end of period of the training, but this changes was not significantly. Interaction variance
(groups × phases) was not significant. Results showed a variance between group WHR is significant
(P<0.05). In addition, during the training, there was no significant change in serum Ferritin levels in both
groups.
Discussion and Conclusions
In the present study, no statistically significant difference was observed in the body mass index of
exercise group subjects' body weight, body mass index and body fat presented. This finding was
supported by researchers (Bouhlel et al., 2008; Pérusse et al., 1997).
In this study, although ferritin concentration reduced but not significant changes were observed in ferritin
levels in both groups, which was consistent with Furqan at al., (2007), Bartfay et al., (1995), Moosavi
Zade (2011) and Furqan at al., (2007) reported moderate physical activity to be more important in
lowering serum ferritin than vigorous activity. Bartfay et al., (1995) demonstrated regular exercise could
decrease serum ferritin concentrations. Moosavi Zade (2011) reported that eight weeks aerobic training
which including 40 minutes running twice a week with%60 to%65 reserve heart rate caused decrease in
serum iron, serum ferritin and transferrin concentration and serum ferritin in girls. Probably reason of
decreasing of RBC and consequently decreasing of HB is due to decreasing of iron serum. Whereas the
concentration of iron serum is reduced body will use from transferrin as reserving iron which can be
probably reason of decreasing of transferring concentration percent. Decreasing of serum ferritin may be
excreting iron in training and may be non- from nutrition. The reason of distinction of results of this
research with other researches could also be the variables such as sex, age, training intensity, training
period length, samples diffusion from point of view of social situation, economic nutrition. Serum ferritin
concentration has been positively associated with body mass index (BMI), alcoholic intake, triglyceride
levels, and diastolic and systolic pressure (Galan et al., 2006; Milman et al., 1999). Particularly in those
with type 2 diabetes, blood serum ferritin concentration has been significantly related to plasma oxidized
LDL, but not with LDL cholesterol (Ikeda et al., 2006). Meanwhile, other researchers have reported a
significant association between ferritin concentration and cholesterol (Galan et al., 2006; Hedley et al.,
2002).
While, other investigations have reported opposing findings, Schumacher et al, (Schumacher et al.,
2002), Rocker et al., (2002). Schumacher et al, (2002), who attributed a increase in serum ferritin
concentration after the laboratory tests for trained and untrained subjects and after prolonged aerobic
Intl. J. Sport Std. Vol., 2 (8), 379-384, 2012
383
exercise in male cyclists in thirty nine subjects. Rocker et al, (2002) concluded that the amount of
hemoglobin, serum ferritin and transferrin values were increased after the endurance race. Due to the
differences in the results of the studies can be related to the different volume and intensity and duration of
the training.
In conclusion, it seems that more researches are required for evaluating the effects of prolong aerobic
exercise on serum ferritin and there are yet many unanswered questions in this relation. We believe that
prolong exercise, due to reduce in serum ferritin. Although more research, as well as basic research and
large-scale epidemiological studies, is required to totally assess the association between iron
concentration and risk of CVD, although the results to date supporting the iron and coronary heart
disease hypothesis are weak and inconsistent.
Acknowledgment
This study was funded by the Research vice-President of Mashhad University; the project was approved
by the Ethics Committee for Scientific Research at the Academy of Physical Education under code
of 1686 in Ferdowsi university of Mashhad, Iran.
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Effect of one period of selective aerobic training on serum, Iron, serum ferritin andtransferrin of girls The aim of this research is finding of the effect of eight weeks selective training on hematological indexes of girls. 13 girls of university students were selected none randomly. In this research effect of eight weeks aerobic training which including 40 minutes running twice a week with%60 to%65 reserve heart rate on serum Iron, serum ferritin andtransferrin were examined. Subjects performed eight weeks trainings. Automatic machines for measuring of iron and ferritin IRMA kit for measuring of ferritin concentration were used. It was seen significant decrease in serum Iron, serum ferritin transferrin in girls (P%5).In final, data were analyzed by t student method. These results were obtained: eight weeks aerobic training caused decrease in serum iron, serum ferritin andtransferrin concentration and serum ferritin in girls (p%5).
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Iron and copper catalyze lipid peroxidation in vitro, and recent epidemiological data suggest that these metal ions might also be involved in human coronary heart disease. We tested the hypothesis by investigating whether the storage proteins ferritin and ceruloplasmin were coronary risk factors. A nested case-control study was set up in middle-aged dyslipidaemic participants of the Helsinki Heart Study: a placebo-controlled coronary primary prevention trial with gemfibrozil Of the 140 subjects with cardiac end-points (non-fatal myocardial infarction or cardiac death) 136 were matched with controls for geographical area and drug treatment (gemfibrozil-placebo). Frozen baseline serum samples were used in the analyses of ferritin and ceruloplasmin. Using logistic regression analyses no increment in coronary risk was detected with increasing ferritin levels (P=0.8 for trend). Ceruloplasmin was higher 349 ± 86 vs 317 ± 77mg. l⁻¹ (P<0.001) in cases than in controls and the risk in the highest fertile was two-fold (odds ratio 21; 95% CI 1.3-4.2) compared to the lowest (P<0.005 for trend). The risk of high ceruloplasmin was influenced by lipoprotein cholesterol concentrations, with an odds ratio of 2.4 (95% CI 1.3-4.4) in subjects with high low density lipoprotein cholesterol and of 11.3 (95% CI 2.5-52.2) in subjects with low high density lipoprotein cholesterol. It was concluded that ferritin was not associated with coronary heart disease in dyslipidaemic, middle-aged men, while there was a continuous and graded increment in coronary risk with elevating ceruloplasmin level.
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To investigate the relationship of serum ferritin with sex and exercise. A cross-sectional design study carried out in Winnipeg, Manitoba. Urban Canadians of Icelandic descent, aged 21 to 60 years, took part in this investigation. Subjects were stratified by age, sex and menstrual status. Venous blood samples from fasting subjects were drawn for serum ferritin, hemoglobin and hematocrit analyses. Various anthropomorphic measurements were taken, and subjects underwent submaximal cycle ergometry testing. A health and lifestyles questionnaire and a four-day prospective food record were administered. Mean serum ferritin levels obtained were 187.93 and 47.84 micrograms/L for males and females, respectively. Mean serum ferritin levels were 33.06 micrograms/L and 71.14 micrograms/L for premenopausal and postmenopausal females, respectively. The mean weekly consumption of alcohol was 190 mL/week and 80 mL/week for males and females, respectively. The mean dietary intake of iron was 27.3 and 18.9 mg/day for males and females, respectively. Males, but not females, who exercised 45 mins or more per week had significantly lower levels of serum ferritin than their sedentary counterparts. In males, hemoglobin, hematocrit and the consumption of alcohol were positively correlated with serum ferritin, while exercise time was negatively correlated with serum ferritin. A trend towards lower serum ferritin levels at higher workloads was observed in males, but did not reach statistical significance. In females, age and dietary intake of iron were found to be positively correlated with serum ferritin, while history of anemia, menstrual status and workload were negatively correlated with serum ferritin. These findings suggest that regular aerobic exercise may decrease iron stores in the body. This may be clinically significant since high serum ferritin has been cited as a risk factor for coronary artery disease.