

Citation: Martínez-Rodríguez, A.;
Miralles-Amorós, L.;
Vicente-Martínez, M.; Asencio-Mas,
N.; Yáñez-Sepúlveda, R.;
Martínez-Olcina, M. Ramadan
Nutritional Strategy: Professional
Soccer Player Case Study. Nutrients
2022, 14, 465. https://doi.org/
10.3390/nu14030465
Academic Editor: Lauri Byerley
Received: 17 December 2021
Accepted: 18 January 2022
Published: 21 January 2022
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nutrients
Article
Ramadan Nutritional Strategy: Professional Soccer Player
Case Study
Alejandro Martínez-Rodríguez 1,2,*
, Laura Miralles-Amorós 1
, Manuel Vicente-Martínez 3,
Nuria Asencio-Mas 1, Rodrigo Yáñez-Sepúlveda 4 and María Martínez-Olcina 1
1
Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Sciences, University of Alicante,
03690 Alicante, Spain; laura.miralles@ua.es (L.M.-A.); niam1@gcloud.ua.es (N.A.-M.);
maria.martinezolcina@ua.es (M.M.-O.)
2
Alicante Institute for Health and Biomedical Research (ISABIAL Foundation), 03010 Alicante, Spain
3
Faculty of Health Science, Miguel de Cervantes European University, 47012 Valladolid, Spain;
mvmartinez11006@alumnos.uemc.es
4
Escuela de Educación, Pedagogía en Educación Física, Universidad Viña del Mar, Viña del Mar 7055, Chile;
rodrigo.yanez@uvm.cl
*
Correspondence: amartinezrodriguez@ua.es
Abstract: The period of Ramadan induces changes in the usual eating patterns of individuals. During
this period, Muslims must abstain from drinking and eating from dawn to dusk. Therefore, some
research conducted on professional soccer players has observed that during and/or after Ramadan,
performance, running speed, agility, dribbling speed, and endurance and/or skill performance in
athletic events may be negatively affected by Ramadan intermittent fasting (RIF). The objective of this
study was to analyze the inﬂuence of a dietary plan during RIF on performance and body composition
in a professional soccer player. A 20-year-old elite player (86.0 kg, 188.5 cm) followed a dietary-
nutritional plan with an isocaloric diet and was supplemented with glycerol. The athlete’s strength
and power in the lower limbs was assessed by performing a countermovement jump (CMJ) and
Abalakov vertical jump (ABK) before and after Ramadan. After nutritional planning, the patient’s
body composition improved in terms of fat loss (6.61 to 5.70%) and muscle mass gain (50.26 to
51.50%). In addition, this translated into improvements in performance tests, both in the CMJ (36.72
to 40.00 cm) and ABK (39.16 to 49.34 cm). In conclusion, during a period of fasting, personalised
nutritional planning and an appropriate supplementation and rest protocol can improve the body
composition and performance of soccer players.
Keywords: nutrition; sport; athletic performance; sports supplements; body composition; dietary tools
1. Introduction
The period of Ramadan induces changes in the usual dietary patterns of individu-
als; during this period, Muslins must abstain from drinking and eating from sunrise to
sunset [1]. According to the Holy Quran, it takes place in the ninth month of the Islamic
calendar, and, as a lunar month, it lasts between 29 and 30 days [2].
According to the Federation International Football Association (FIFA), soccer has pro-
moted fair play, heterogeneity and fairness and is an internationally recognized sport [1].
The month of Ramadan often coincides with the calendars of many soccer leagues [1].
Researchers have proceeded to conduct studies on adult and youth Muslim soccer players
because of their commitment to their faith and the game. It has been shown that, dur-
ing and/or after Ramadan, performance, running speed, agility, dribbling speed, and
endurance and/or skill performance in athletic tests can be negatively affected by Ramadan
intermittent fasting (RIF) [3,4].
In the same way, sleep duration is compromised, as dinners and breakfasts are usually
early during Ramadan [5,6]. Indeed, by altering the sleep-wake cycle of circadian rhythms,
Nutrients 2022, 14, 465. https://doi.org/10.3390/nu14030465
https://www.mdpi.com/journal/nutrients
Nutrients 2022, 14, 465
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a modiﬁcation in anticipation and adaptation to environmental changes occurring during
the day may occur in the metabolism and cardiovascular system [2]. Therefore, biological
rhythms and how they affect human performance must be taken into account, as some
factors, such as hepatic and muscular glucogen stores, ﬂuid stores, decreased blood glucose
levels, increased uric acid and the risk of dehydration during prolonged physical activity,
could negatively impair athletic performance [7].
Currently, there are no studies evaluating the effects of Ramadan that intervene at
the dietary-nutritional level, so there are still no adapted plans for practitioners practicing
RIF [1,8]. However, the variation in total energy intake before and after Ramadan has
been evaluated [6,9,10]. In these investigations, it has been observed that the intake was
insufﬁcient to meet the needs of the athletes and, in addition, the estimated total daily
energy intake and the relative proportions of carbohydrate, fat and protein in the diet did
not change during Ramadan in the participants [6,9,10].
Physical performance tests such as counter movement jump (CMJ) and Abalakov
jump are often used in these investigations to assess recovery from baseline levels and
serve to measure power and fatigue [11,12]. Results for CMJ have been inconclusive in
the literature [8]. Rebaï et al. [13] observed signiﬁcant increases in CMJ during Ramadan;
the increases were signiﬁcant during versus before Ramadan for the group that reduced
their training load. However, some of the studies found do not evaluate the effect of RIF on
Abalakov’s jumping tests, with free arm jumps being predominant in this sport [9,10,13].
Another aspect that inﬂuences sports performance and can be affected by RIF is body
composition. In soccer, it is important to control body fat, as optimal fat levels allow players
to move more efﬁciently during training and matches [11,14]. Further relevant is the lean
mass compartment, speciﬁcally muscle mass, because insufﬁcient or excessive training
loads can impact the physique, affecting performance, as well as speed, strength, power
and injury risk [15].
Although inconsistent ﬁndings on body composition for RIF have been observed in
the scientiﬁc literature [1,8], some studies use data obtained from bioimpedance or the
summation of 4 folds [6,9]. In addition, other research proposes, but does not carry out, the
complete proﬁle of 5 components: skin, body fat, muscle mass, bone tissue and residual
mass. This model allows to get a photographic shape of the athlete’s proﬁle [16].
Another aspect that lacks research so far is the medio somatotype and the Heath and
Carter anthropometric method classiﬁcation [17] for Muslim RIF performers.
In order to respond to all these gaps in the scientiﬁc literature, the main objective of this
research was to describe the effects of RIF with personalized dietary-nutritional planning
on the athletic performance and body composition of an elite soccer player. The initial
hypothesis was that performance would be negatively affected by the month of Ramadan.
2. Materials and Methods
2.1. Study Design
A case report was used to analyse the inﬂuence of RIF on performance and body
composition in a professional soccer player. In this design, an initial measurement prior to
the intervention (start) and a measurement after the intervention (ﬁnal) was conducted.
The participant was informed about the possible risks and discomforts that could arise
and was asked to complete a health history questionnaire and sign a consent form. The
research strictly followed the Declaration of Helsinki (Edinburgh review in 2000), and the
procedures were also in accordance with the recommendations of the EEC Good Clinical
Practice (document 111/3976/88 of July 1990). The subject signed an informed consent to
participate in the study after receiving all the information. All procedures were previously
approved by the Ethics Committee of the University of Alicante (UA-2021-03-11).
2.2. Participant
The participant was a 20-year old African soccer player since he was 5 years old,
having now 15 years of experience. He has been playing soccer at a professional level, for
Nutrients 2022, 14, 465
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the team in La Liga for the last two seasons. He usually trains 12 h per week and his only
dedication is soccer. He is healthy, does not take any medication, has never undergone
surgery and has an optimal blood biochemistry.
2.3. Data Collection
2.3.1. Body Composition
Body weight was measured early in the morning, fasting and with minimal clothing,
using a Tanita BC-545n, (Tanita Corporation, Arlington Heights, IL, USA) to the near-
est 0.1 kg. Standing height without shoes was measured using a Seca 213 stadiometer
(Seca, Hamburg, Germany) to the nearest 0.1 cm. To minimize the potential source of
Bioimpedance systems (BIA) related to total body weight and height, body composition
assessment was performed by a level three anthropometrist following the International
Society for the Advancement of Kinanthropometry (ISAK) recommendations [18]. All mea-
surements were performed at the same location, at room temperature and under baseline
conditions. The technical error of measurement for perimeters, circumferences, lengths and
heights was less than 1% and less than 5% for skinfolds.
Anthropometric measurements were performed following the complete proﬁle of ISAK
II methodology [18]. Skinfolds, girths, lengths and breadths were measured with a caliper,
ﬂexible metallic tape, segmometer and pachymeter, respectively (Holtain, Crymych, UK).
Bone and muscle mass were obtained through Rocha’s equation [19] and Lee’s for-
mula [20], respectively. Fat mass was estimated using Carter’s formula [21], Faulkner
formula [22] and Withers’ equation [23]. Residual mass was calculated from the difference
between the total body weight minus the sum of the bone, muscle and fat masses. Accord-
ing to the Spanish Committee of Kinanthropometry, these methods are the most suitable
for high performance players [24].
Somatotype components were calculated from the assessment of different body com-
partments, including fat mass for endomorphy, muscle mass for mesomorphy, and leanness
and relative bone linearity for ectomorphy. The differences between each individual so-
matopoint with respect to the mean value was calculated using the somatotype attitudinal
mean (SAM) [25,26].
Proportionality analyses were performed using the Phantom stratum [19]. Each
variable was ﬁtted to the Phantom size using the z-score. The z-values have a mean of 0, so
a z-value of 0.0 indicates that the given variable is proportionally equal to the Phantom; a z-
value greater than 0.0 means that the subject is proportionally greater than the Phantom for
that variable; and, conversely, a z-value less than 0.0 shows that the subject is proportionally
less than the Phantom for the variable [19].
2.3.2. Performance Measures
As indicators of global strength, the countermarch jump (CMJ) and the Abalakov
jump test [27] were performed. In the CMJ test, the participant performed a maximal
vertical jump starting from a standing position, without allowing the arms to swing, and
bending the knees 90◦. The participant performed several familiarisation trials prior to
the test [28]. A contact platform (Optojump Next Microgate, Bolzano, Italy) was used to
measure the CMJ. Three measurements were performed with 30 s recovery in between. The
ﬂight time was used to calculate the jump height. The best jump was used for subsequent
analysis [29,30].
The Abalakov jump test followed the same protocol. The participant also performed
3 countermovement jumps with 30 s rest between jumps, on a platform with an optical
(infrared) data collection system (Optojump Next Microgate, Bolzano, Italy) to calculate
the Abalakov jump height [31]. The player had to stand up and perform a 90◦ knee ﬂexion
followed by the fastest extension to reach the highest possible jump height. Of the three
results, the best one was used for statistical analysis.
Nutrients 2022, 14, 465
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2.4. Nutritional Intervention Protocol
2.4.1. Nutrient Intake
For the dietary-nutritional intervention, quantitative estimates were made of total
energy expenditure based on basal metabolism, using the Harris–Benedict formula [32]
and corrected body weight. Physical activity expenditure was estimated from standardized
factors [33]. The proposed diet was based on an isocaloric intake following the recommen-
dations for elite soccer players [34].
Table 1 shows the values of macronutrients and vitamin B12 provided by the dietary-
nutritional guideline established according to the recommendations for elite soccer players.
Fiber intake was around 25 g per day and total cholesterol was less than 200 mg per day. The
software used in the elaboration of the diet was Dietopro (Dietopro, Valencia, Spain) [35].
Table 1. Dietary nutrient intake.
Calories (Kcal)
3432.1
Carbohydrates (g)
398.1
Proteins (g)
219.4
Fat (g)
112.7
Vitamin B12 (mg)
17.3
Carbohydrates (g/kg/day)
4.6
Protein (g/kg/day)
2.5
PFA/MFA
1.2
Kcal = kilocalories; g = grams; kg = kilograms; PFA = polyunsaturated fatty acids; MFA = monounsaturated
fatty acids.
Because the time of ingestion is different than usual during the RIF, a schedule was
established with SK for each of the different meals (Table 2).
Table 2. Meal times.
Intake
Time of Day
Breakfast
5:30–6:00
Snack
20:00
Dinner
22:30
Snack
0:30
2.4.2. Supplementation
Glycerol (1,2,3-propanetriol) is produced from glucose, protein, pyruvate, triacylglyc-
erols and other glycerolipid metabolic pathways and is a binding metabolite in numerous
pathways [27].
During RIF, glycerol is the only source of gluconeogenesis, as glycogen stores are
depleted within two days of fasting [28]. Considering its role as an energy substrate,
glycerol could effectively improve sports performance [28]. The combined ingestion of
glycerol and ﬂuid has been used to increase body water volume, thus maintaining hydration
by reducing the rate of water elimination from the kidneys [27]. The intake protocol is
shown in Table 3.
Table 3. Glycerol intake protocol.
Time
Glycerol (g)
Liquid (L)
1–3 days
25
0.5
4–6 days
50
1
7–10 days
75
1.5
11–ﬁnal
100
2
g = grams; L = liters.
Nutrients 2022, 14, 465
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3. Results
3.1. Body Composition
The soccer player remained weight-stable throughout the study period (the initial
weight was 86.1 kg, while at the end of the intervention the weight reached 85.9 kg).
The athlete claimed to have followed the entire nutritional plan, based on 3400 kcal,
4.6 g/kg/day of carbohydrates and 2.5 g/kg/day of protein.
Table 4 shows the results of the body composition assessment between the beginning
and the end of the RIF. It can be observed that both weight and fat mass percentage
decreased after the intervention. However, muscle mass increased (from 50.26 to 51.50%).
The somatotype presented is ecto-mesomorphic, where mesomorphy predominates and
ectomorphy is higher than endomorphy.
Table 4. Body composition results.
Body Composition
Start
Final
Weight (kg)
86.1
85.9
Height (cm)
188.5
188.5
BFM Carter (%)
3.80
3.30
BFM Faulkner (%)
9.30
8.90
BFM Withers + Siri (%)
6.61
5.70
Muscle mass (kg) Lee 2000
43.27
44.20
Muscle mass (%) Lee 2000
50.26
51.50
Bone mass (kg) Rocha
13.96
14.01
Bone mass (%) Rocha
16.21
16.31
Residual mass (kg)
23.18
22.81
Residual mass (%)
26.92
26.55
Endomorphy
1.38
1.16
Mesomorphy
5.46
5.98
Ectomorphy
2.67
2.69
BFM: Body Fat Mass; kg = kilograms; cm = centimeters; % = percentage.
With regard to skinfolds, the triceps (4.5 to 3.5 mm), subscapular (8.2 to 7.6 mm),
biceps (3.4 to 2.5 mm), supraspinal (4.5 to 4.2 mm), abdominal (5.8 to 4.8 mm), thigh (6.3
to 6.1 mm) and leg (4.3 to 2.8 mm) skinfolds decreased, while the triceps (4.3 to 2.8 mm)
skinfold decreased, (5 to 4.2 mm), abdominal (5.8 to 4.8 mm), thigh (6.3 to 6.1 mm) and leg
(4.3 to 2.8 mm) decreased, while the iliac crest crease increased (6.1 to 6.4 mm).
Differences were observed in the different variables for anthropometric dimensions
and proportionality proﬁle. The results for Z-perimeter calf (0.06 to 0.20), Z-perimeter thigh
(−0.08 to −0.25), Z-perimeter hip (−0.95 to −1.72), Z-perimeter waist (−1.17 to −1.20),
Z-perimeter forearm (1.96 to 2.28), Z-perimeter ﬂexed arm (2.49 to 3.15) and Z-perimeter
relaxed arm (1.98 to 2.06) were higher after the intervention. However, the Z-perimeter
mesosternale decreased from −0.28 to −0.20.
3.2. Sport Performance
Regarding sport performance results, lower limb power measured with the CMJ and
Abalakov jumps tests shows a considerable improvement in performance after the RIF and
the dietary-nutritional intervention performed. The variation of the Abalakov jump was
from 39.16 to 49.34 cm, while the countermovement jump improved from 36.72 to 40 cm.
4. Discussion
The main objective of this research was to evaluate body composition, physical con-
dition (through different physical tests) and a personalized dietary-nutritional plan in a
professional soccer player at the beginning and at the end of the Ramadan period.
Differences in daily energy intake among different studies could be due to dietary
habits, cultural customs, biopsychosocial environment, and geographical differences of the
study participants. The present ﬁndings demonstrate that the estimated total daily energy
Nutrients 2022, 14, 465
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intake was not affected by Ramadan fasting, since the player followed the dietary pattern,
where the nutritional plan was adapted to the fasting schedule [29–31].
In terms of body composition, the player presented lower initial characteristics of
muscle mass and higher fat mass compared to the end of the study. This can also be seen in
the measurement of skinfolds, where all decreased, except for the iliac crest. So far, no study
has analyzed these parameters in such depth. Only one study by Durnin and Womersley
et al. [36] analyzed the sum of 4 skinfolds (triceps, biceps, subscapular and suprailiac); it
was observed that there was no signiﬁcant difference after the RIF period [37]. Another
investigation by Meckel et al. [9] found a slight increase in skinfolds. These studies did not
include the implementation of a personalized dietary plan, so the results may be due to an
inadequate diet.
It should be noted that this is the ﬁrst study to investigate the effect of a dietary-
nutritional planning adapted to Ramadan on lower limb physical performance variables
and 5-component body composition. This study consists of the CMJ and Abalakov jump
tests, being the ﬁrst study to evaluate Abalakov in a Muslim professional athlete. In
reference to the scores, all were higher after the intervention. Therefore, the player had
better lower body power at the end of the study than at the beginning. These results at
ﬁrst indicate an increase in physical performance tests, however, they are different from
those obtained in previous studies, as some studies showed that Ramadan fasting decreases
physical performance [9,37], while others revealed no effect [3,4,6].
Furthermore, since Abalakov tests can be used as a performance indicator and as part
of the selection process of youth soccer players for national teams [38], future research
should include this test in its variables.
On the other hand, some researchers [27] underline the importance of the qualities of
glycerol for success in aerobic and anaerobic activities, emphasizing the effect on perfor-
mance, since it can be used as an energy substrate. The ﬁndings of such supplementation
evidence its relevance and usefulness in the athlete population, since it has been observed
that hypohydration decreases maximal aerobic power [27]. Therefore, the effects of such
supplementation could have had a positive impact on the performance tests of the subject
included in the present study, following the same line as other investigations [39].
Existing scientiﬁc evidence shows that adequate hydration and nutrition are essential
to improve performance in soccer during Ramadan periods [1,40]. It should be borne in
mind that soccer is a high-intensity intermittent sport played in hot environments, so there
is an increased risk of dehydration, with sweating rates in elite players of 1–2.5 L/h [39].
Therefore, both physiological function and cognitive and athletic performance are com-
promised. To maximise the effects of training during Ramadan and better adapt to the
conditions presented, it is essential to make appropriate dietary choices, ensuring optimal
energy intake during periods of high-intensity, long-duration training [1].
The results of this case study should be interpreted with caution, as they are based on
the performance of a single athlete using an experimental protocol (n = 1) in which neither
the participant nor the researchers were unaware of the project during the intervention
phase. In fact, only one set of performance tests was conducted at the beginning and end of
the intervention. Future research will consider the previously mentioned limitation. It is
recommended that researchers in the ﬁeld provide more detailed information on ﬁtness
assessment, body composition and dietary habits in future studies on professional soccer
players and the RIF, as research is still scarce.
5. Conclusions
During a fasting period such as Ramadan, an optimal and personalized nutritional
planning according to the demands and needs of each athlete, accompanied by a supple-
mentation of glycerol and rest protocol, allows for improvements on body composition and
lower limb performance indicators in soccer players.
Author Contributions: Conceptualization, A.M.-R. and M.M.-O.; methodology, A.M.-R. and R.Y.-S.;
software, M.V.-M.; validation, R.Y.-S. and A.M.-R.; formal analysis, M.M.-O.; investigation, M.M.-O.,
Nutrients 2022, 14, 465
7 of 8
L.M.-A., N.A.-M. and M.V.-M.; resources, M.V.-M.; data curation, L.M.-A. and N.A.-M.; writing—
original draft preparation, M.M.-O. and L.M.-A.; writing—review and editing, A.M.-R. and R.Y.-S.;
visualization, M.V.-M.; supervision, A.M.-R.; project administration, A.M.-R. All authors have read
and agreed to the published version of the manuscript.
Funding: This research received no external funding.
Institutional Review Board Statement: The study was conducted according to the guidelines of the
Declaration of Helsinki and also approved by the Ethics Committee of the University of Alicante
(UA-2021-03-11, 26 June 2021).
Informed Consent Statement: Written informed consent has been obtained from the patient(s) to
publish this paper.
Data Availability Statement: The data presented in this study is available on request from the
corresponding author. The data are not publicly available due to is personal health information.
Acknowledgments: To the European Institute of Exercise and Health (EIEH) of Alicante University
for their selﬂess collaboration in this research.
Conﬂicts of Interest: The authors declare no conﬂict of interest.
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Ramadan Nutritional Strategy: Professional Soccer Player Case Study.
Martínez-Rodríguez, Alejandro,Miralles-Amorós, Laura,Vicente-Martínez, Manuel,Asencio-Mas, Nuria,Yáñez-Sepúlveda, Rodrigo,Martínez-Olcina, María