Abstract

Introduction: Nutritional supplements and ergogenic aids (NS&EA) are used between training/matches with the goal of enhancing tennis performance. Scientific literature about prevalence and use of NS&EA in professional tennis players is scarce. Objective: The aim of the study was to describe the NS&EA used by professional tennis players during a season. Methods: Using a validated self-administered questionnaire, 62 professional male and 9 professional female tennis players (11% in their gender specific top 100 tennis world ranking (i.e.,ATP/WTA)) registered all the used NS&EA. Results: Eighty-one percent of the participants declared taking at least one NS&EA. Strength and conditioning trainers (S&C) and tennis coaches were the professionals who recommended most of the NS&EA in the players outside the TOP-100 (OT100; 50.7% and 39.1%, respectively). However, sports nutritionist were the principal advisors in the top-100 tennis players (T100; 62.5%). Sports drinks were the NS&EA most commonly used by all participants (81.7%). T100 participants used caffeine (p = 0.042), creatine (p = 0.001), iron (p = 0.013) and CHO-protein mix (p = 0.033) significantly more frequently that OT100 players. Conclusions: There is a high prevalence of NS&EA use among professional tennis players independently of their tennis ranking position. However, T100 tennis player have an increased use of certain substances such us caffeine, creatine, iron and CHO-Protein mix. For the rest of the studied NS&EA the use was similar between T100 and OT100 players. It is possible that the differences in NS&EA use between groups could be related to the different professionals on charge of nutritional advice in T100 vs OT100.
Nutrición
Hospitalaria
Nutr Hosp. 2017; 34(6):xxxx-xxxx ISSN 0212-1611 - CODEN NUHOEQ S.V.R. 318
Trabajo Original Otros
Correspondence:
Juan Fernando Ortega Fonseca.
Exercise Physiology Lab. Faculty of Sports Sciences.
Universidad de Castilla-La Mancha.
Avda. Carlos III, s/n. 45071 Toledo, Spain
e-mail: juanfernando.ortega@uclm.es
López-Samanes Á, Moreno-Pérez V, Kovacs MS, Pallarés JG, Mora-Rodríguez R and Ortega JF. Use of
nutritional supplements and ergogenic aids in professional tennis players. Nutr Hosp 2017;34:xxxx-xxxx
DOI: http://dx.doi.org/10.20960/nh.1404
We would like to thank to all participants for their uninterested participation in this project and Joan
Sacristan from Nutrisport S.A.
Use of nutritional supplements and ergogenic aids in professional tennis players
Título español
Álvaro López-Samanes 1,2, Víctor Moreno-Pérez3, Mark S. Kovacs4,5, Jesús G. Pallarés1,6, Ricardo Mora-Rodríguez1 and Juan F. Ortega1
1Exercise Physiology Laboratory at Toledo. University of Castilla-La Mancha. Toledo, Spain. 2School of Physiotherapy. School of Health Sciences. Francisco de Vitoria
University (UFV). Madrid, Spain. 3Sports Research Center. Miguel Hernández University. Elche, Spain. 4International Tennis Performance Association (ITPA). Georgia, USA.
5Life Sports Science Institute. Life University. Marrietta, Georgia. USA. 6Human Performance and Sports Science Laboratory. University of Murcia, Spain
Key words:
Nutrition. Tennis.
Ergogenic aids.
Palabras clave:
Nutrición. Tenis.
Ayudas ergogénicas.
Resumen
Introducción: los suplementos nutricionales/ayudas ergogénicas (NS&EA) son utilizados en los entrenamientos/partidos de tenis con el objetivo
de mejorar el rendimiento. Sin embargo, la literatura científica se encuentras escasos documentos científicos sobre el uso de estas sustancias
en tenistas profesionales.
Objetivo: describir el uso de NS&EA utilizados por tenistas profesionales durante una temporada.
Métodos: se utilizó un cuestionario validado y se evaluó a 62 tenistas profesionales hombres y 9 mujeres (11% entre los 100 mejores del mundo).
Resultados: el 81% de los participantes toman al menos un NS&EA. Los preparadores físicos (S&C) y entrenadores de tenis fueron los profe-
sionales preferidos para recomendar NS&EA entre los jugadores fuera del TOP-100 (OT100, 50,7% y 39,1%, respectivamente). Sin embargo,
los nutricionistas deportivos fueron los principales asesores de los jugadores entre los 100 mejores del mundo (T100, 62,5%). Las bebidas
deportivas fueron los NS&EA más utilizados entre todos los participantes (81,7%). Los tenistas T100 utilizaron cafeína (p = 0,042), creatina (p =
0,001), hierro (p = 0.013) y mezcla de CHO-proteína (p = 0,033) significativamente más frecuentemente que los jugadores OT100.
Conclusiones: existe una gran prevalencia de uso de NS&EA entre los tenistas profesionales. Además, los T100 presentan un mayor uso de
ciertas sustancias tales como cafeína, creatina, hierro y CHO-proteína. Para el resto de los NS&EA estudiados, el uso fue similar entre los juga-
dores T100 y OT100. Finalmente, las diferencias en el uso de NS&EA entre grupos pudieran estar relacionadas con los diferentes profesionales
escogidos para el asesoramiento nutricional en T100 vs. OT100.
Abstract
Introduction: Nutritional supplements and ergogenic aids (NS&EA) are used between training/matches with the goal of enhancing tennis
performance. Scientific literature about prevalence and use of NS&EA in professional tennis players is scarce.
Objective: The aim of the study was to describe the NS&EA used by professional tennis players during a season.
Methods: Using a validated self-administered questionnaire, 62 professional male and 9 professional female tennis players (11% in their gender
specific top 100 tennis world ranking (i.e., ATP/WTA)) registered all the used NS&EA.
Results: Eighty-one percent of the participants declared taking at least one NS&EA. Strength and conditioning trainers (S&C) and tennis coaches
were the professionals who recommended most of the NS&EA in the players outside the TOP-100 (OT100; 50.7% and 39.1%, respectively).
However, sports nutritionist were the principal advisors in the top-100 tennis players (T100; 62.5%). Sports drinks were the NS&EA most commonly
used by all participants (81.7%). T100 participants used caffeine (p = 0.042), creatine (p = 0.001), iron (p = 0.013) and CHO-protein mix (p =
0.033) significantly more frequently that OT100 players.
Conclusions: There is a high prevalence of NS&EA use among professional tennis players independently of their tennis ranking position. However,
T100 tennis player have an increased use of certain substances such us caffeine, creatine, iron and CHO-Protein mix. For the rest of the studied
NS&EA the use was similar between T100 and OT100 players. It is possible that the differences in NS&EA use between groups could be related
to the different professionals on charge of nutritional advice in T100 vs OT100.
Received: 03/07/2017
Accepted: 18/09/2017
1025USE OF NUTRITIONAL SUPPLEMENTS AND ERGOGENIC AIDS IN PROFESSIONAL TENNIS PLAYERS
[Nutr Hosp 2017;34(6)::xxxx-xxxx]
INTRODUCTION
In recent years, the interest of nutritional supplements (NtS) and
ergogenic aids (EA) has dramatically increased in the sports arena. NtS
are defined as concentrated sources of nutrients or other substances
with a nutritional or physiological effect beyond what is supplemented
by a normal diet (1), while EA are pharmacological agents used for
the purpose of enhancing sports performance (2). Commercial brands
have found a profitable market where high performance athletes (3),
university students (4) and young amateur athletes (5) avidly supple-
ment their diets with these type of products. Increasing prevalence of
NtS and EA use among athletes has alerted health and sports author-
ities, since a non-negligible amount of NtS and EA are contaminated
with harmful/banned substances (6). This could endanger athlete’s
health or cause competition ban if containing doping substances (7).
Although the use of NtS and EA is generalized in all the spectrum of
performance (i.e., from recreational to elite athletes), only a few EA
(e.g., creatine, sodium bicarbonate, caffeine) have been demonstrated
to result in enhanced sports performance (8).
Tennis is an intermittent sport which combines short-high intensi-
ty efforts with moderate to low intensity periods (i.e., active recovery
between points and passive recovery between games), over variable
periods of time (i.e., 1-5 hours) (9). Tennis performance depends of the
interaction among technical, tactical, physical and psychological factors
(10) which includes nutritional aspects (2). In addition, environmental
conditions (11) play a relevant role in tennis success. Recently, time-
of-day has been proposed as a factor which could modify physical
tennis performance (12). Top 100 tennis players compete on average
25 tournaments per year around the world (13). Travelling through dif-
ferent time-zones added to the high physical demands of professional
tennis competition, represent a challenge in the sports nutrition field
in order to find recovery strategies aimed to maintain the competitive
level during the whole season. Although general guidelines for nutrition
and recovery interventions in tennis have been developed (14), there
are scarce evidence about nutritional interventions to improve tennis
performance and/or recovery among matches and training sessions.
To our knowledge there are two recent reviews on the issue of nutri-
tional supplements in tennis, one by Ranchordas et al. (15) and the other
by Lopez-Samanes et al. (2). However, there are no reports of NtS and
EA use specifically among professional tennis players. Thus, the first
objective of this study was to describe the use of NtS and EA in males
(i.e., ATP) and female (i.e. WTA) professional tennis players. The second
objective of this study was to compare NtS and EA intake between
tennis players inside and outside the top 100 world ranking. The present
study is a retrospective-observational study, however, possible differenc-
es between the studied groups might represent nutritional/ergogenic
factors which could be useful to characterize elite tennis players.
METHODS
PARTICIPANTS
Seventy-one professional tennis players, 62 male tennis players
(87.3%) and 9 female tennis players (12.7%) accepted to participate
in the study. Within volunteers, 5 tennis male players and 3 female
players were in the top 100 worldwide ranking (T100) (age 29.1 ± 4.6
years, height 1.76 ± 0.08 m, body weight 74.1 ± 10.5 kg, age started
tennis 6.4 ± 1.1 years, numbers of hours training tennis 15.5 ± 3.3
hours/week and number of hours of physical conditioning 11.0 ± 2.0
hours/week) whereas the remaining participants (57 men and 6 women)
ranked at position between 300-2000 at the ATP/WTA roster (OT100)
(age 20.6 ± 4.2 years; height, 1.80 ± 0.07 m; body weight, 72.2 ±
7.2 kg, age at start of tennis training 6.6 ± 2.8 years, volume of training
tennis 14.8 ± 5.9 hours/week and volume of physical conditioning 6.5
± 3.3 hours/week). It is worth to mention that is considered as a profes-
sional, any tennis player who has achieved at least 1 ATP/WTA point (16).
Thus, all players we tested were professional according to the ATP/WTA.
The study complied with the declaration of Helsinki and was approved by
the Bioethics Commission of the University of Murcia (Spain).
EXPERIMENTAL DESIGN
Fifty-two participants (73.2%) were recruited during two interna-
tional tennis federation (ITF) Men´s Futures Tournaments and one ITF
Women’s Futures Tournament with money-prices of $10000 USD.
Eleven players (15.5%) were recruited by telephone and nine volun-
teers through e-mail (11.3%). Participants recruited during the tour-
naments filled out a printed version of a closed nutritional/ergogenic
product use questionnaire, whereas the rest of the participants filled
out the electronic version sent by e-mail. For the volunteers recruited
during the tournaments body weight and body-fat percentage were
measured using a wall-mounted stadiometer (Seca 202, Seca Ltd.,
Hamburg, Germany) and an electronic scale which includes bioimped-
ance analysis for body composition (Tanita B-601, Tanita Corp., Tokyo,
Japan). Regarding the volunteers contacted via phone/e-mail, body
composition data were provided by one member of the player’s tech-
nical staff using similar equipment.
QUESTIONNAIRE
A 4-page questionnaire was developed to assess the frequency,
dose and types of NtS and EA used by professional tennis players,
based in two questionnaires previously validated (3,17). The question-
naire was divided in two different sections. The first section assessed
the frequency and dose of NtS and EA taken by tennis players, as well
as the reasons for taking them and who did advice its consumption
(e.g., sports nutritionists, strength and conditioning coaches, coaches,
athletic trainers, other players, etc.). The second part specifies the NtS
and EA used by the athlete such as minerals, energy drinks, protein
and branched amino-acids (BCAA), vitamins, and short-chain or omega
3-fatty acids among others.
STATISTICAL ANALYSIS
Data are presented as means and standard deviation (SD) for
the participant’s characteristics, whereas frequencies and per-
1026 Á. López-Samanes et al.
[Nutr Hosp 2017;34(6):xxxx-xxxx]
centages are used for the rest of the data. Shapiro-Wilk test a
normal distribution of recorded data. Baseline characteristics
comparisons between players inside and outside world ranking
(T100 and OT100, respectively) were analysed using T-test for
independent samples. Comparison of frequencies between T100
and OT100 players were assessed by chi-square (χ²). Statistical
significance was set as P < 0.05.
RESULTS
NTS AND EA USE AMONG PROFESSIONAL
TENNIS PLAYERS
Data revealed that 81.3% of the professional tennis players
take at least one NtS or EA. The most frequently NtS and EA used
by the studied athletes are displayed in table I. In both groups
sport drinks were the most used NtS (87.5% and 81.0% for T100
and OT100 groups, respectively). Supplementation with proteins
and minerals were commonly used by T100 participants, since
all the T100 participants supplemented their diet with proteins,
whereas 80% of the T100 participants used minerals supple-
mentation. On the other hand, OT100 participants showed lower
frequencies of use for proteins (58%) and minerals (56%). In
comparison to OT100 participants, T100 participants showed
higher use of iron (p = 0.013), creatine (p = 0.001), caffeine (p
= 0.042) and CHO-protein mix (p = 0.033). Use of legit ergogenic
aids is displayed in table II. Regarding the frequency of use of NtS
and EA, a daily use of NTs or EA was reported in 87.5% of T100
players, and in 52.4% of OT100 players, whereas a weekly use
of NtS or EA was reported in 25.0% of T100 players and 7.9% of
OT100 players. It is remarkable that some NtS as sports drinks
are commonly used daily, whereas some EA and mineral supple-
mentation (e.g., iron) are used sporadically during the season.
PRESCRIPTION/RECOMMENDATION OF NTS
AND EA
Data regarding the source of advice for prescription/recommenda-
tion of NtS and EA among participants is displayed in table III. Strength
and conditioning coaches (S&C) (50.7%) and tennis coaches (39.1%)
were the professionals who mainly recommended the NtS and EA
use for OT100 players, while for T100 volunteers, NtS and EA were
recommended mainly by a Sports Nutritionist (62.5%). Only among
the OT100 players it was observed that family members, friends and
internet web sites were information sources for NtS and EA use.
REASONS FOR NTS AND EA USE
Reasons for NtS and EA use are displayed in table IV. For both,
T100 and OT100 participants, recovery between efforts (50.0%
and 59.4% respectively) and increase of energy levels (50.0%
and 43.5% respectively) were the main reasons behind the NtS
and EA use. Aesthetics reasons (i.e. enhance body image) was
reported as a reason to use NtS in 9.4% of the OT100 players,
but in any of the T100 players.
DISCUSSION
Nutrition and training are determinant factors in the overall per-
formance of tennis players. However, the scientific literature in
the field of nutritional supplements and ergogenic aids applied to
competitive tennis players is scarce. To our knowledge, this is the
first study presenting a descriptive analysis of the consumption of
NtS and EA in a group of professional tennis players. Prevalence
of NtS and EA use in other sports has been previously reported,
however none of them totally resembles the demands and par-
ticularities of tennis. Nevertheless, we found that the prevalence
of NtS and EA use (81.7%) is in general agreement with data
collected in studies conducted in athletes from several sports
Table I. Most frequently used nutritional
supplements and ergogenic aids among
elite tennis players. T100, Top 100
players; OT100, outside top 100 players.
Data are frequencies (percentage)
T100 (n = 8) OT100 (n = 63)
Sports drinks 7 (87.5%) 51 (81%)
CHO-protein mix 5 (62.5%)* 14 (22.2%)
Iron 5 (62.5%)* 4 (6.3%)
Mineral-vitamin complex 4 (50%) 18 (27.6%)
Caffeine 4 (50%) 7 (11.1%)
Protein shakes 2 (25%) 25 (39.7%)
*Significantly different to the OT100 group at p < 0.05.
Table II. Use of legit ergogenic aids
among professional tennis players.
T100, Top 100 players; OT100, outside
top 100 players. Data are frequencies
(percentage)
TOP 100
(n = 8)
OT 100
(n = 63)
p
value
Creatine 6 (75%)* 7 (11.1%)* 0.001
Caffeine 4 (50%)* 7 (11.1%)* 0.042
L-Carnitine 0 (0%) 5 (7.93%) 0.412
L-Arginine 1 (12.5%) 3 (4.76%) 0.211
Sodium bicarbonate 0 (0%) 3 (4.76%) 0.532
B-Alanine 0 (0%) 2 (3.17%) 0.612
*Significantly different to the OT100 group at p < 0.05.
1027USE OF NUTRITIONAL SUPPLEMENTS AND ERGOGENIC AIDS IN PROFESSIONAL TENNIS PLAYERS
[Nutr Hosp 2017;34(6)::xxxx-xxxx]
were conducted on athletes from different sports. The prevalence
of NtS and EA use presently reported in professional tennis players
is higher than the described in other intermittent sports such
basketball with (58%) (24). It seems that sports characteristics
determine in part the use of NtS and EA. Thus, in cyclic sports of
moderate-intensity long-duration, athletes seem to be more prone
to use carbohydrates and vitamins (25), while athletes who take
part in explosive intense sports where actions are short (i.e., Gael-
ic Football), seem to consume ergogenic aids such as caffeine and
creatine (26). Our findings indicate that elite tennis players (i.e.,
top 100 world ranking) show a higher prevalence of ergogenic
aids use than the rest of the professional tennis players, indicating
possibly the availability of a different grade of nutritional advice.
Professional tennis players interact with tennis coaches,
strength and conditioning coaches, nutritionists, physical thera-
pists, physicians, and other players being those the main source
of advice on nutritional/ergogenic supplements. Regarding the
person responsible for recommendation/prescription of NtS and
EA, our data from tennis players outside top 100 (OT100) are
in agreement with previous investigations carried out in college
athletes of several sports which indicated that strength and condi-
tioning coaches are the main source of NtS/EA recommendation/
prescription (27). However, for tennis players within the top 100
(T100), sports nutritionist, were the most consulted professional
(Table IV). It is possible that the reason for the differences found
in the person responsible for recommendation/prescription of NtS
and EA among players inside and outside T100 could be simply
availability, since T100 players with more professional success
can use their larger economic resources to hire sports nutritionist
for their team.
Sports drinks are the most common NtS used by professional
tennis players, either in the T100 and OT100 participants. Surpris-
ingly, the scientific literature is contradictory about the benefits of
sports drinks on tennis performance. Some authors have reported
positive tennis performance when providing sports drinks (28),
whereas other authors did not find benefits (29). Some substances
showed a higher prevalence of use among the T100 in compari-
son to OT100 tennis players. One of these substances is creatine
(75% vs. 11.1%, p = 0.001), which has been recognized as an
useful ergogenic aid to enhance sports performance both, in cycli-
cal and intermittent sports (30). However, several authors have
not found evidences of tennis performance improvement after
creatine use. Eijnde and co-workers studied the effects of creatine
(i.e., 4 doses x 5 grams) or placebo in a group of tennis players
in a double-blind, cross-over design (31). After compare serve
accuracy and running velocity on a 70 m shuttle run test, they did
not find differences between the creatine and placebo conditions.
More recently, Pluim et al. (32) confirmed this findings, in a ran-
domized and double-blind study. They provided a creatine loading
dose of 0.30 grams/kg body weight/day and a maintenance dose
of 0.03 grams/kg body weight/day, and compare the results from
a complete specific tennis test-battery. The test included serve
velocity, muscular strength, intermittent running speed pre-and
post-intervention. Their results showed that creatine ingestion
did not improve any of the variables measured. Thus, although
Table IV. Reasons for taking nutritional
supplements and ergogenic aids among
professional tennis players. T100, Top 100
players; OT100, outside top 100 players.
Data are frequencies (percentage)
TOP 100
(n = 8)
OT 100
(n = 63)
Recovery between efforts 4 (50%) 38 (59.4%)
Increase energy levels 4 (50%) 28 (43.5%)
Prevent nutritional deficiency 2 (25%) 6 (9.4%)
Health maintenance 1 (12.5%) 24 (37.5%)
Enhance immunity 1(12.5%) 4 (6.3%)
Medical indications 1 (12.5%) 2 (3.1%)
Increase lean body mass 0 (0%) 20 (31.3%)*
Enhance body image 0 (0%) 6 (9.4%)
*Significantly different to the OT100 group at p < 0.05.
Table III. Source of advice for
prescription/recommendation of
nutritional supplements and ergogenic
aids among professional tennis players
T100, Top 100 players; OT100, outside
top 100 players. Data are frequencies
(percentage)
T100 (n = 8) OT100 (n = 63)
Sports Nutritionist 5 (62.5%) 6 (9.4%)
S&C Coach 3 (37.5%) 32 (50.7%)
Teammates 2 (25%) 10 (15.6%)
Medical Doctor 1 (12.5%) 14 (21.9%)
Tennis Coach 1 (12.5%) 25 (39.1%)
Physiotherapist 2 (25%) 8 (12.5%)
Family 0 (0.0%) 5 (7.8%)
Friends 0 (0.0%) 4 (6.3%)
Internet 0 (0.0%) 2 (3.1%)
disciplines (18). Kondric et al. (19) reported in non-professional
tennis players that 80% of the male participants and 100% of the
female volunteers consumed NtS. However, in their paper, Kondric
et al. did not provide data about which NtS were used, the person
responsible for the prescription/recommendation of the NtS or
the frequency of use. On the other hand, the finding that NtS or
EA use is highly prevalent among athletes is not universal. While
some studies report a high prevalence (97-98%) in the use of NtS
or EA (20,21), other authors showed use between 51% and 59%
(22,23). It is worth to mention that the previously cited studies
1028 Á. López-Samanes et al.
[Nutr Hosp 2017;34(6):xxxx-xxxx]
creatine use is highly prevalent on professional tennis players,
mainly those inside the T100, there is no hard evidence about its
efficacy to improve tennis performance.
Caffeine is another substance that we found to be highly prev-
alent within the T100 tennis players group (p = 0.042), but no
used so frequently in OT100 tennis players (Table II). Caffeine is
a well-accepted ergogenic aid for improving sports performance
(33). Early studies by Graham and co-workers revealed that doses
between 3-6 mg/kg improved cycling endurance performance
(34). By measuring contraction velocity during resistance exercise,
we have recently reported that caffeine could also increase neu-
romuscular performance (35). Lastly, a number of studies using
GPS tracking devices support that caffeine could increase the
number of high-speed actions during intermittent sports (e.g.,
soccer) (36), the cited results could be interesting from the tennis
performance perspective, since tennis is characterized by high
intermittent bouts of effort. Evidence about the benefits of caffeine
in tennis performance are building, since time of day (i.e., morn-
ing) shows a detrimental effect on some features related with ten-
nis performance (12), and caffeine has been shown to counteract
the effect of morning reduction of performance in athletes. Some
studies have reported several benefits (i.e. increased handgrip
force, running pace at high intensity and number of sprints during
a simulated match) with caffeine ingestion (37) but other studies
have not reported any benefit (38) on performance.
Iron supplementation use showed large differences in con-
sumption between the T100 vs. OT100 (62.5% vs. 6.3%, p =
0.013). However, the iron use in the 3 of the T100 tennis players
studied was the result of a medical prescription to treat haema-
tological conditions. Iron prescription is highly prevalent in female
runners (39) and athletes from sports with a high aerobic demand.
Specifically in tennis players, Ziemann et al. (40) reported that
around 50% of young athletes present ferritin concentrations
below the reference range. Thus, we could hypothesize that the
higher prevalence of iron supplementation observed among T100
players could be related with the accessibility to medical screening
and in consequence detection of iron deficiencies, which could be
limited in players OT100.
Improvement of recovery between efforts and increase of energy
levels were the most reported reasons among tennis players. This
finding could be related to their demanding competition calendar,
since during a regular season, professional tennis players inside top
100 compete in average in 25 tournaments. In some tournaments,
they must compete twice per day to face the single and doubles
matches. Thus, recovery between matches seems to be crucial to
maintain performance. There is available a comprehensive review
about this issue (14). It is remarkable that a non-negligible num-
ber of OT100 players include increases of lean body mass and
enhancement of body image as reasons for NtS and EA use. Those
reasons were not reported in any of the T100 players possibly indi-
cating a different state of focusing and motivations between groups.
In summary, we present novel findings about the high preva-
lence of nutritional supplements and ergogenic aids use among
professional tennis player. Sports drinks are the most common
nutritional supplements used by players top 100 or below top 100
professional tennis players. In addition, we found that professional
tennis players inside the top 100 ranking obtain recommenda-
tion/prescription mainly from sport nutrition professional, whereas
the rest of players receive this advice from their coaches, due
probably to budget constraints. As a result, professional tennis
players within the 100 ATP use more creatine, caffeine iron and
CHO-protein mix, than players below 100 ATP, in spite of the fact
that scientific evidence supporting the use of creatine for tennis
performance is lacking. The main reasons for tennis players to
use supplements and ergogenic aid is to speed recovery between
competitions which evidences the need for these aids for their
demanding competition calendar.
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... Although there are two reviews which talk about nutritional supplements in tennis, one by Ranchordas et al. (2013) [18] and the other by López-Samanes et al. (2015) [19], as well as a recent article on NS consumption in professional tennis players [20], there is very little literature which assesses NS consumption in amateur tennis players. The objective of the present study was to evaluate NS consumption in a group of amateur tennis players who participated in the men's category at the 2016 Andalusian team championship. ...
... The most frequently reported reasons to justify NS consumption by participants were, to improve their athletic performance (87.1%) and to alleviate some dietary deficit (46.8%). Although not necessarily in the same order of priority, similar results had been found in other studies in which improving sports performance [20,[25][26][27] and mitigating some dietary deficits [20,25,28] were some of the most frequently reported justifications for NS consumption by athletes. ...
... The most frequently reported reasons to justify NS consumption by participants were, to improve their athletic performance (87.1%) and to alleviate some dietary deficit (46.8%). Although not necessarily in the same order of priority, similar results had been found in other studies in which improving sports performance [20,[25][26][27] and mitigating some dietary deficits [20,25,28] were some of the most frequently reported justifications for NS consumption by athletes. ...
Preprint
Literature on the use of nutritional supplements (NS) in tennis players is scarce. The objective of the present study was to evaluate NS consumption in a group of men's tennis players who participated in the 2016 Andalusian team championship. A total of 70 questionnaires from 7 different clubs were registered. The questionnaire was previously designed and evaluated through piloting in which the validity of the content, its application, its structure and its presentation were observed. The results showed that 100% of the sample group was in favor of NS consumption within the law, 88.6% claimed to have consumed them at some time and 61.4% presently consume them. The NS most consumed by study participants were sports drinks (69.35%), energy bars (29%), a vitamin complex (19.35%), protein (serum) (17.74%) and creatine (14.51%). A high percentage of NS consumers thought that they had obtained positive results from NS consumption. The percentages and the findings regarding NS consumption in the present study were similar to the contributions made by other studies which evaluated supplementation in athletes, although with some subtle differences.
... Aunque no hubo diferencias significativas, sin tener en cuenta el nivel competitivo, la razón principal del uso de suplementos deportivos para los jugadores masculinos de balonmano fue para mejorar el rendimiento deportivo, mientras que la razón más frecuente en las jugadoras de balonmano femeninas fue obtener un beneficio para la salud. Una tendencia similar se ha informado previamente en muestras de deportistas de élite (López-Samanes et al., 2017b;Sousa et al., 2013;Caraballo, Domínguez, Guerra-Hernández y Sánchez-Oliver, 2020) que podrían respaldar la idea de que, a pesar de tener una prevalencia similar en el uso de suplementos deportivos, las razones para usar suplementos deportivos son ligeramente diferentes entre deportistas hombres y mujeres, siendo estás últimas las que normalmente están más preocupadas por los suplementos que producen un beneficio para la salud. Además, una mayor proporción de jugadores profesionales de balonmano usaron suplementos para aumentar el rendimiento (51,9%) que los jugadores amateurs (34,0%). ...
... En relación con el sitio de compra de los suplementos deportivos, se observaron diferencias dependiendo del nivel competitivo de los jugadores. Las tiendas especializadas en nutrición eran el lugar preferido de compra para los profesionales y para los jugadores amateurs de balonmano (Sánchez-Oliver, Además, en comparación con los jugadores amateurs, una alta proporción de jugadores profesionales de balonmano se basó en las opiniones de sus preparadores físicos para el uso de suplementos deportivos (López-Samanes et al., 2017b), mientras que médicos o nutricionistas fueron consultados con menos frecuencia. Asimismo, una proporción considerable de jugadores de balonmano amateurs, en comparación con los jugadores profesionales, se basaron en sí mismos o en la información obtenida a través de internet para planificar el uso de suplementos deportivos. ...
... Respecto a los suplementos deportivos más consumidos por los jugadores de balonmano fueron las bebidas deportivas, seguidas de las barritas energéticas y productos que contienen cafeína, teniendo un patrón de consumo muy similar para jugadores masculinos y femeninos y para ambos niveles competitivos (ver Tabla 3 y 4). Según la literatura consultada, parece normal que las bebidas deportivas y las barritas energéticas se encuentren dentro de los suplementos deportivos más populares en diferentes deportes intermitentes (e.g., squash y tenis) (López-Samanes et al., 2017b;Ventura-Comes et al., 2018), probablemente debido al gran nivel de evidencia científica que hay sobre estos suplementos deportivos sobre la efectividad de la ingesta exógena de carbohidratos para mejorar el rendimiento deportivo (Baker, Rollo, Stein y Jeukendrup, 2015). En este caso, la cafeína fue consumida por un tercio de la muestra de jugadores de balonmano, con una proporción similar en jugadores profesionales y amateurs y entre jugadores de balonmano de hombres y mujeres. ...
Thesis
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Suplementación Deportiva en Balonmano: Efecto de la Cafeína e Influencia del CYP1A2 y ADORA2A en el Rendimiento Deportivo en Jugadores de Élite de Balonmano
... The proportion of SS consumption differs greatly depending on a multitude of variables, such as the sports modality that has the greatest difference between them (30-95%) (16,20). Although our study's results place SS consumption within this range (46.9%), this was lower than similar populations from other sports modalities that reported consumption between 64% and 81.7% (18,21,26,27). This places SS consumption within our sample of elite fencers below the ndings of recent studies that have evaluated the consumption of SS in elite athletes. ...
... The current hypothesis is that fencers at a higher level of competition (20) who are male (28) consume more SS. However, the results obtained in our study do not show a signi cant difference between national and international fencers, which contrasts with studies in which there are signi cant differences international-level athletes (11,18,20,23,26). Similarly, no differences were observed in the prevalence of SS use among athletes according to sex, which is in line with the ndings of the meta-analysis by Knapik et al. (2016) (20). ...
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Background The aim of this study was to analyze the consumption of sports supplements (SS) in competitive level fencers and compare differences based on sex and competitive level (international and national). Methods A total of 49 fencers (18 men and 31 women) of national (n= 16) and international (n= 33) level completed a questionnaire with questions about SS consumption and the possible repercussions on health and / or sports performance. The results were analyzed based on the different categorizations established by the Australian Institute of Sport (AIS), as well as by sex and level of competence to which the participants belonged to. Results 46.9% of fencers have consumed SS with the main motivation being performance improvement (34.2%). Medical doctors were the individuals who were more likely to advise men to consume SS (50.0% vs 5.6%; OR = 3.29 [1.50-7.20]). Friends were most likely to advise women (38.9% vs 8.3%; OR = 1.75 [1.05-2.93]). The most consumed SS were sport drinks (44.9%), vitamin C (43.4%), sport bars (38.8%), and caffeine (28.6%). In regards to the SS categories, it was observed differences in the interaction level·sex in medical supplements (p = 0.017). In addition, there was a higher prevalence of whey protein consumption in women (25.8% vs 0%; p = 0.020) and iron consumption in men (33% vs 6.5%; p = 0.039). Conclusions The prevalence of SS use in fencers is within the values previously reported in athletes of the same competitive level. There were no differences by sex and competitive level in the total consumption of SS, nor in each of the groups of level of evidence, being sport drinks, bars and caffeine the most consumed SS.
... It should be noted that the results found in the present study support the hypothesis that suggests both an increased DS consumption with a higher level of training or competition and a higher consumption in males compared to females [19], two of the variables that most influence the consumption of DS [24,38]. Furthermore, these results are similar to those reported in different studies that have detected a higher consumption in males [18,27,38] and athletes with a higher level of competition [18,24,26,39,40]. ...
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Purpose: the aim of the present study was to analyse the pattern of dietary supplements (DS) consumption on federated rugby players, including the analysis of differences based on the sex and competitive level (professional vs. amateurs). Material and methods: 144 rugby players (83 male and 61 female), of whom 69 were professionals and 75 amateurs, were recruited for the study. All the participants filled out a specific questionnaire about DS consumption including questions related to the consumption of DS and their effects on sport performance and health status. Results: 65.3% of participants declared consuming at least one DS, with a higher prevalence in males than females (77.1% vs. 49.2%) and in professionals thanin amateur players (79.7% vs. 52.0%). The main reason for consumption was to enhance sport performance (62.3%) with differences only based on sex (74.3% males vs. 43.2% females). The most common purchase sites were the Internet (45.6%) and specialised stores (39.8%). As to the moment of ingestion, professionals did this most frequently during competition and training (56.4% vs. 28.2%), whereas amateur players did so only during competition (20.5% vs. 3.6%). Moreover, professional player intake most frequently in post-exercise (65.5% vs. 35.9%), whereas amateur during pre-exercise (30.8% vs. 5.5%). The DS most consumed included whey protein (44%), caffeine (42%), sports drinks (38%), energy bars (34%) and creatine monohydrate (31%), with a higher prevalence in male and professional players of whey protein and creatine monohydrate. Conclusions: The main reason for DS consumption is for enhancing sports performance). Professional players more frequently purchase them on the Internet and consume DS during training and competition period and in the post-exercise, whereas amateur players consume during competition and pre-exercise. Related to the main form of DS consumption, it is observed that a moderate consumption of DS could be considered ergogenic, such as whey protein, sport bar and creatine, while an absence of other DS could be considered ergogenic.
... Commonly, creatine monohydrate supplementation has been used as a strategy to increase muscle mass and strength during training, but it has been also reported to improve power and anaerobic capacity [48][49][50]. Thus, the use of creatine in intermittent sports such as racquet sports is of high interest since about 75% of top 100 rank tennis players take it [17]. However, up to the present, there is no evidence for recommendation. ...
Article
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A nutritional ergogenic aid (NEA) can help athletes optimize performance, but an evidence-based analysis is required in order to support training outcomes or competition performance in specific events. Racquet sports players are regularly exposed to a high-intensity workload throughout the tournament season. The activity during a match is characterized by variable durations (2–4 h) of repeated high-intensity bouts interspersed with standardized rest periods. Medline/PubMed, Scopus, and EBSCO were searched from their inception until February 2020 for randomized controlled trials (RCTs). Two independent reviewers extracted data, after which they assessed the risk of bias and the quality of trials. Out of 439 articles found, 21 met the predefined criteria: tennis (15 trials), badminton (three trials), paddle (one trial), and squash (two trials). Among all the studied NEAs, acute dosages of caffeine (3–6 mg/kg) 30–60 min before a match have been proven to improve specific skills and accuracy but may not contribute to improve perceived exertion. Currently, creatine, sodium bicarbonate, sodium citrate, beetroot juice, citrulline, and glycerol need more studies to strengthen the evidence regarding improved performance in racquet sports.
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Background: The aim of this study was to analyze the consumption of sports supplements (SS) in competitive level fencers and compare differences based on sex and competitive level (international and national). Methods: A total of 49 fencers (18 men and 31 women) of national (n = 16) and international (n = 33) level completed a questionnaire with questions about SS consumption and the possible repercussions on health and / or sports performance. The results were analyzed based on the different categorizations established by the Australian Institute of Sport (AIS), as well as by sex and level of competence to which the participants belonged to. Results: 46.9% of fencers have consumed SS with the main motivation being performance improvement (34.2%). Medical doctors were the individuals who were more likely to advise men to consume SS (50.0% vs 5.6%; OR = 3.29[1.50–7.20]). Friends were most likely to advise women (38.9% vs 8.3%; OR = 1.75 [1.05–2.93]). The most consumed SS were sport drinks (44.9%), vitamin C (43.4%), sport bars (38.8%), and caffeine (28.6%). In regards to the SS categories, it was observed differences in the interaction level·sex in medical supplements (p = 0.017). In addition, there was a higher prevalence of whey protein consumption in women (25.8% vs 0%; p = 0.020) and iron consumption in men (33% vs 6.5%; p = 0.039). Conclusions: The prevalence of SS use in fencers is within the values previously reported in athletes of the same competitive level. There were no differences by sex and competitive level in the total consumption of SS, nor in each of the groups of level of evidence, being sport drinks, bars and caffeine the most consumed SS.
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Sports supplements are commonly used by elite athletes with the main goal of enhancing sport performance. Supplements use might be substantially different depending on the sport discipline, sex, and competitive level. To date, data about prevalence and the most-commonly used supplements in handball are scarce. Thus, the aim of this investigation was to determine the patterns of supplements use by handball players of both sexes and with different competitive levels: One hundred and eighty-seven handball players (112 men and 75 women) of different competitive levels (106 professional and 81 amateur) completed a validated self-administered questionnaire about supplements use. Supplements were classified according to the categorization of the Australian Institute of Sport (AIS). Overall, 59.9% of the handball players (n = 112) declared the use of at least one supplement and there were no significant differences between men and women (58.9% vs. 61.3%, p = 0.762) nor between professional vs. amateur handball players (67.1% vs. 53.8%, p = 0.074). The most prevalent supplements were sports drinks (42.2%), followed by energy bars (35.3%) and caffeine-containing products (31.6%). However, a greater consumption of group A supplements (those with strong scientific evidence; p = 0.029) and group B supplements (those with emerging scientific support, p = 0.012) was observed in male compared to female handball players. Supplements categorized as medical supplements were more commonly consumed in professional vs. amateur players (0.48 ± 0.80 vs. 0.21 ± 0.44, supplements p < 0.006). Additionally, a higher consumption of group B supplements was observed in professional compared to amateur players (0.58 ± 0.88 vs. 0.33 ± 0.72 supplements, p = 0.015). Handball players revealed a moderate use of supplements while sex and competitive level slighted changed the pattern of supplements use. A high portion of handball players use supplements as fuel during exercise and reported the use of caffeine-containing supplements to enhance performance.
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A nutritional ergogenic aid (NEA) can help athletes optimize performance, but an evidence-based analysis is required in order to support training outcomes or competition performance in specific events. Racquet sports players are regularly exposed to a high-intensity workload throughout the tournament season. The activity during a match is characterized by variable durations (2-4 h) of repeated high-intensity bouts interspersed with standardized rest periods. Medline/PubMed, Scopus, and EBSCO were searched from their inception until February 2020 for randomized controlled trials (RCTs). Two independent reviewers extracted data, after which they assessed the risk of bias and the quality of trials. Out of 439 articles found, 21 met the predefined criteria: tennis (15 trials), badminton (three trials), paddle (one trial), and squash (two trials). Among all the studied NEAs, acute dosages of caffeine (3-6 mg/kg) 30-60 min before a match have been proven to improve specific skills and accuracy but may not contribute to improve perceived exertion. Currently, creatine, sodium bicarbonate, sodium citrate, beetroot juice, citrulline, and glycerol need more studies to strengthen the evidence regarding improved performance in racquet sports.
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Professional tennis is a highly competitive sport ranked through an objective, merit-based, mathematical system. The objective of this study was to determine and analyze how top 1°-ranked professional tennis players perform in the previous three years. Data of ranking position of all top 1°-ranked female and male players in the professional era and their performance in Grand Slams tournaments were collected from tennis stakeholders’ websites and analyzed. Top 1° male players’ ranking position averaged 2.17 ± 1.92 (CI 95%:1.56/2.78), 7.02 ± 18.073, and 10.73 ± 29.31, at 1, 2, and 3 previous years, respectively. Top 1° female players’ ranking position averaged 2.21 ± 1.59 (CI 95%:1.61/2.71), 4.78 ± 4.09, and 14.97 ± 26.75, at 1, 2, and 3 previous years, respectively. All top 1° male and female players were ranked within the 1°-10° and 1°-6° positions the previous year, respectively; the majority of tennis champions won at least one Grand Slam tournament during the year before reaching the top 1° ranking position (females = 69%; males = 65%), and during the same season (females = 82%; males = 92%). Female and male top 1°-ranked player maintained that position in the following year in 48.7% and 52.5% of cases, respectively. In conclusion, tennis players need to perform at high level during at least three years prior to reach the top 1° position in the professional tennis ranking. Both, male and female champions, showed similar patterns of performance in their professional career.
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To determine the effect of circadian rhythm on neuromuscular responses and kinematics related to physical tennis performance, after a standardised warm-up, 13 highly competitive male tennis players were tested twice for serve velocity/accuracy (SVA), countermovement vertical jump (CMJ), isometric handgrip strength (IS), agility T-test (AGIL) and a 10-m sprint (10-m RUN). In a randomised, counter-balance order, tennis players underwent the test battery twice, either in the morning (i.e., AM; 9:00 h) and in the afternoon (i.e., PM; 16:30 h). Paired t-tests were used to analyse differences due to time-of-day in performance variables. Comparison of morning versus afternoon testing revealed that SVA (168.5 ± 6.5 vs. 175.2 ± 6.1 km · h⁻¹; P = 0.003; effect size [ES] = 1.07), CMJ (32.2 ± 0.9 vs. 33.7 ± 1.1 cm; P = 0.018; ES = 1.46), AGIL (10.14 ± 0.1 vs. 9.91 ± 0.2 s; P = 0.007; ES = 1.23) and 10-m RUN time (1.74 ± 0.1 vs. 1.69 ± 0.1 s; P = 0.021; ES = 0.67) were significantly blunted during the morning testing. However, IS was not affected by time-of-day (P = 0.891). Thus, tennis performance may be reduced when competing in the morning in comparison to early evening. Therefore, coaches and tennis players should focus on schedule the SVA, power, speed and agility training sessions in the afternoon.
Article
This study analyzed the effects of pseudoephedrine (PSE) provided at different time of day on neuromuscular performance, side effects, and violation of the current doping cut-off threshold [World Anti-Doping Agency (WADA)]. Nine resistance-trained males carried out bench press and full squat exercises against four incremental loads (25%, 50%, 75%, and 90% one repetition maximum [1RM]), in a randomized, double-blind, cross-over design. Participants ingested either 180 mg of PSE (supra-therapeutic dose) or placebo in the morning (7:00 h; AMPLAC and AMPSE) and in the afternoon (17:00 h; PMPLAC and PMPSE). PSE enhanced muscle contraction velocity against 25% and 50% 1RM loads, only when it was ingested in the mornings, and only in the full squat exercise (4.4–8.7%; P < 0.05). PSE ingestion raised urine and plasma PSE concentrations (P < 0.05) regardless of time of day; however, cathine only increased in the urine samples. PSE ingestion resulted in positive tests occurring in 11% of samples, and it rose some adverse side effects such us tachycardia and heart palpitations. Ingestion of a single dose of 180 mg of PSE results in enhanced lower body muscle contraction velocity against low and moderate loads only in the mornings. These mild performance improvements are accompanied by undesirable side effects and an 11% risk of surpassing the doping threshold.
Article
The aim of this study was to investigate the effectiveness of a caffeinated energy drink to enhance physical performance in elite junior tennis players. In two different sessions separated by one week, 14 young (16±1 years) elite level tennis players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo drink). After sixty minutes, participants performed a handgrip strength test, a maximal velocity serving test, an 8×15 m sprint test and then played a simulated singles match (best of 3 sets). Instantaneous running speed during the matches was assessed using global positioning devices (GPS) devices. Furthermore, the matches were video-taped and notated afterwards. In comparison to the placebo drink, the ingestion of the caffeinated energy drink increased handgrip force by ~4.2±7.2% (P=0.03) in both hands and the running pace at high intensity (46.7±28.5 vs 63.3±27.7 m·h-1; P=0.02) and the number of sprints (12.1±1.7 vs 13.2±1.7; P=0.05) during the simulated match. There was a tendency for increased maximal running velocity during the sprint test (22.3±2.0 vs 22.9±2.1 km·h-1; P=0.07) and higher percentage of points won on service with the caffeinated energy drink (49.7±9.8 vs 56.4±10.0%; P=0.07) in comparison to the placebo drink. The energy drink did not improve ball velocity during the serving test (42.6±4.8 vs 42.7±5.0 m·s-1; P=0.49). The pre-exercise ingestion of caffeinated energy drinks was effective to enhance some aspects of the physical performance of elite junior tennis players.
Article
Gaelic football is the second most popular team sport in Ireland in terms of participation. However, very little research exists on the nutritional considerations for elite male Gaelic footballers. Gaelic football is an intermittent type field game played by two teams of fifteen players. Although amateurs, elite players may train and compete 4-5 times per week and may play for several teams. Research suggests that elite footballers are similar anthropometrically and in fitness to professional soccer players. Work-rate analysis shows that footballers experience longer durations of high-intensity (HI) activity (5-7s) and shorter rest durations than soccer players. Recent data suggests that half-forwards/backs perform a greater amount of HI work during games than players in other positions. Fatigue is apparent between the first and second halves and the first and fourth quarters. The limited amount of nutritional studies conducted implies that footballers may be deficient in energy intake and may be at the lower end of recommended carbohydrate intakes to support training. A wide variety of sweat rates have been measured during training, demonstrating the importance of individual hydration strategies. Ergogenic aids such as creatine and caffeine may prove beneficial to performance, although data is extrapolated from other sports. Due to the lack of research in Gaelic football, further population specific studies are required. Future areas of research on the impact of nutrition on Gaelic football performance are examined. In particular, the creation of a test protocol mimicking the activity patterns and intensity of a Gaelic football game is warranted.