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A number of intermittent team sports require that two consecutive periods of play (lasting for ~30-45 min) are separated by a 10-20 min half-time break. The half-time practices employed by team-sports players generally include returning to the changing rooms, temporarily relaxing from the cognitive and physical demands of the first half, rehydration and re-fuelling strategies, addressing injury or equipment concerns, and receiving tactical instruction and coach feedback. However, the typically passive nature of these actions has been associated with physiological changes that impair performance during the second half. Both physical and cognitive performances have been found to decline in the initial stages of subsequent exercise that follows half-time. An increased risk of injury has also been observed during this period. Therefore, half-time provides sports scientists and strength and conditioning coaches with an opportunity to optimise second-half performance. An overview of strategies thought to benefit team-sports athletes is presented; specifically, the efficacy of heat maintenance strategies (including passive and active methods), post-activation potentiation, hormonal priming, and modified hydro-nutritional practices are discussed. A theoretical model of applying these strategies in a manner that compliments current practice is also offered.
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Half-Time Strategies to Enhance Second-Half Performance
in Team-Sports Players: A Review and Recommendations
Mark Russell Daniel J. West Liam D. Harper
Christian J. Cook Liam P. Kilduff
ÓSpringer International Publishing Switzerland 2014
Abstract A number of intermittent team sports require
that two consecutive periods of play (lasting for
*30–45 min) are separated by a 10–20 min half-time
break. The half-time practices employed by team-sports
players generally include returning to the changing rooms,
temporarily relaxing from the cognitive and physical
demands of the first half, rehydration and re-fuelling
strategies, addressing injury or equipment concerns, and
receiving tactical instruction and coach feedback. How-
ever, the typically passive nature of these actions has been
associated with physiological changes that impair perfor-
mance during the second half. Both physical and cognitive
performances have been found to decline in the initial
stages of subsequent exercise that follows half-time. An
increased risk of injury has also been observed during this
period. Therefore, half-time provides sports scientists and
strength and conditioning coaches with an opportunity to
optimise second-half performance. An overview of strate-
gies thought to benefit team-sports athletes is presented;
specifically, the efficacy of heat maintenance strategies
(including passive and active methods), post-activation
potentiation, hormonal priming, and modified hydro-
nutritional practices are discussed. A theoretical model of
applying these strategies in a manner that compliments
current practice is also offered.
Key Points
Passive half-time practices impair performance in
the initial stages of the second half of team-sports
The efficacy of heat maintenance strategies, post-
activation potentiation, hormonal priming, and
modified hydro-nutritional practices have been
shown in isolated studies.
1 Introduction
A number of intermittent team sports, such as Association
football (soccer), rugby league and union, Gaelic sports
(e.g. Gaelic football and hurling), team handball, field
hockey and Australian rules football are played over con-
secutive periods (normally 30–45 min durations) that are
separated by a temporary pause in play at the mid-way
point; a period known as half-time which is 10–20 min
long. While the regulations of the various sports dictate the
practices that can be performed during half-time, empirical
observations highlight that players primarily aim to relax
mentally from the cognitive and physical demands of the
first half of match-play, rehydrate and re-fuel, attend to
M. Russell (&)
Department of Sport, Exercise and Rehabilitation, Health and
Life Sciences, Northumbria University, Northumberland Street,
Newcastle-upon-Tyne NE1 8ST, UK
D. J. West L. D. Harper
Health and Life Sciences, Northumbria University,
Newcastle-upon-Tyne NE1 8ST, UK
C. J. Cook
School of Sport, Health and Exercise Sciences,
Bangor University, Bangor, UK
L. P. Kilduff
Applied Sports Technology Exercise and Medicine Research
Centre (A-STEM), Swansea University, Swansea, UK
Sports Med
DOI 10.1007/s40279-014-0297-0
injury or equipment concerns, engage in personal reflec-
tion, and receive tactical instruction and coach feedback in
preparation for the second half. Indeed, Towlson et al. [1]
reported that soccer players primarily return to the dressing
room to engage in tactical discussion, receive medical
treatment and consume nutritional ergogenic aids during
the half-time break.
However, during the initial stages of the second half,
numerous authors have reported that reductions in key
aspects of team-sport performance occur. For example,
Mohr et al. [2] showed that as many as 20 % of elite soccer
players have their least intense 15-min period in a match
during the initial part of the second half. Weston et al. [3]
also highlighted that selected physical performance mark-
ers of soccer players and referees decreased between 45
and 60 min when compared with the first 15 min of soccer
match-play. In respect to cognitive performance, as very
often success in team sports is determined by the profi-
ciency of skilled actions, the increase in response accuracy
observed during the first 30 min of intermittent exercise
was attenuated upon restarting exercise after half-time [4].
It therefore appears that half-time practices influence sub-
sequent performance during the initial stages of the second
half, a statement supported by intervention studies that
have demonstrated that attenuated losses in body temper-
ature lead to favourable responses in isolated performance
tests and game-related activities [5,6].
A significant increase in injury risk has also been
reported in the first 20 min of the second half [7]. Analysis
of ten Premier League soccer matches has highlighted that
of the injuries occurring in the second half, the greatest
number of actions causing injury were elicited in the first
15 min of this period [8]. Additionally, Ekstrand et al. [9]
have reported that the incidence of soccer-match injuries
show an increasing tendency over time in both the first and
second halves. Interestingly, the perception of increased
injury risk immediately after the half-time break is also
shared by practitioners involved in the delivery of half-time
activities for soccer players [1].
Factors contributing to increased injury risk are likely
multifaceted; however, Greig [10] reported that while the
concentric strength of both the knee extensors and flexors
was maintained throughout 90 min of intermittent tread-
mill running, a speed-dependent fatigue effect observed in
indices of eccentric hamstring strength did not normalise
during a passive half-time period. Specifically, when using
isokinetic dynamometry, eccentric peak torque measure-
ments taken after half-time were reduced when compared
with the start of the recovery period, a finding that was
statistically significant at higher movement speeds. As a
result, the authors postulated that susceptibility to muscular
strain injury is likely to increase during explosive ballistic
actions, such as those requiring high levels of acceleration
and deceleration. Notably, the number of deceleration
efforts performed in the first 15 min of the second half of
soccer match-play is lower than that observed during the
opening phase of a match [11].
Evidence from studies that have employed passive half-
time practices further highlight the subsequent impairments
of performance capacities observed throughout the second
half [3,5,6,1214]. Consequently, the physiological
changes relating to muscle (T
) and core (T
) tempera-
ture [6,1316], acid-base balance [17] and glycaemic
response [1820] which arise from passive periods com-
parable in length to those observed during half-time (i.e.
*15 min) may therefore contribute to a reduction in play
performance in the first part of the second half. Notably,
Krustrup et al. [21] observed a *1.3 °C reduction in
quadriceps T
during half-time in assistant soccer referees.
Although a desire to enforce tactical superiority [22] and
residual ergogenic effects resulting from the warm-up [23]
have been cited to artificially elevate the pace of play in the
initial stages of a match and thus influence subsequent
comparisons to observations made during this interval [12],
transient reductions in performance during the initial stages
of the second half have been confirmed using a more robust
statistical approach (i.e. when variables are expressed in
relative and thus comparable terms: mmin
)[12]. It is
therefore clear that half-time provides an additional
opportunity on the day of competition to optimise perfor-
mance during the second half.
However, as time pressures, cooperation of the coach/
manager and concerns over impairing a player’s psycho-
logical preparations have been cited as barriers to the use of
specific ergogenic strategies during the half-time period
[1], it is clear that any modification to half-time protocols
must complement current practice. The time-course of
activities performed during a typical half-time period is
outlined in Fig. 1. Although likely to vary between dif-
ferent sports and according to individual team practices,
Towlson et al. [1] reported that *2 min of the soccer half-
time period consists of player’s making their way back to
the changing rooms. Thereafter, although tactical de-
briefing and medical and nutritional practices occupy the
most time (*5 min), personal preparation, addressing
playing kit/equipment concerns, receiving video feedback
and engaging in player/coach interactions also occur during
this break in play. Additionally, a *3-min period of re-
warm-up activities that are performed either on the pitch or
within the stadia may precede the second half of soccer
match-play [1].
In summary, although often considered crucial for pri-
marily tactical reasons, physiologically, half-time can be
viewed as a recovery period following the previous bout of
match-play, a preparatory period preceding subsequent
competition, or a period of transition between the two
M. Russell et al.
halves [24]. Given the transient changes in physical and
cognitive performance that have been found to occur fol-
lowing the half-time break [24,6,12,14], and the evi-
dence which suggests that the perception [1], and incidence
[7,8], of injury risk is elevated in the initial stages of the
second half, half-time provides an additional opportunity
on the day of a match to influence subsequent competitive
performance. Therefore, the purpose of this review was
twofold: (1) to present an overview of the literature
examining practices that may have application to the half-
time strategies of players involved in team sports; and (2)
to provide a theoretical model of application of such
strategies in the context of current practice. Computerised
literature searches were performed in the PubMed, Google
Scholar and SPORTDiscus databases between May 2014
and November 2014. The following keywords were used in
different combinations: ‘half time’, ‘recovery’, ‘soccer’,
‘football’, ‘rugby’, ‘handball’, ‘Gaelic’, ‘hockey’, ‘poten-
tiation’, ‘performance’, ‘hydration’, ‘carbohydrate’, ‘caf-
feine’, ‘priming’, ‘heat maintenance’, ’re-warm up’, ‘warm
up’, ‘testosterone’. All titles were scanned and relevant
articles were retrieved for review. In addition, the reference
lists from both original and review articles retrieved were
also reviewed and relevant publications known to the
authors were also obtained.
2 Half-Time Strategies to Enhance Second-Half
Performance in Team-Sports Players
2.1 Heat Maintenance Strategies
Nearly every athletic competition is preceded by a warm-
up. Typically, varying intensities of exercise, dynamic
stretching and technical practice are performed so that
preparedness for subsequent activity is optimised. While
the ergogenic effects of the warm-up have been proposed
to relate to non-temperature-related mechanisms (e.g. ele-
vated baseline oxygen consumption, post-activation
potentiation [PAP], increased mental preparedness, etc.
[25,26]), previous research also highlights the role of T
on performance.
Notably, Mohr et al. [6] observed initial elevations of
both T
and T
during the first half of a soccer match;
however, during a passive half-time period both T
dropped in excess of 1 °C. Sargeant [27] highlighted
the importance of changes in T
on subsequent perfor-
mance by demonstrating that every 1 °C reduction in T
corresponded to a 3 % reduction in lower-body power
output. Moreover, findings from studies reporting attenu-
ated losses of T
and concomitant protection of physical
performance in team-sports players following an active re-
warm-up [5,6,13] further substantiate the importance of
attenuating body temperature losses during half-time.
However, despite an acknowledgement that attenuating
losses in body temperature impact positively on subsequent
exercise performance, intermittent sports players do not
frequently use active re-warm up strategies in the applied
setting [1]. Indeed, despite periods of warm-up preceding
the first half of competition, only 58 % of practitioners
questioned have reported performing re-warm-up activities
before the second half, a finding that may be attributed to
the limited time (*3 min) available for such activities [1].
Furthermore, a lack of co-operation from the coach/man-
ager and a perceived negative impact upon the psycho-
logical preparations of players have also been proposed as
barriers to explain the inconsistent use of an active re-
warm-up during the half-time period. Additionally, in
sports such as rugby where the number of collisions is high,
considerable time may also be required for provision of
Fig. 1 Current model of strategies employed during a typical 15-min half-time period
Half-Time Strategies in Team Sports
medical attention at half-time. Therefore, half-time prac-
tices that are easily administered and which attenuate
temperature loss and thus protect the temperature-related
mechanisms that aid subsequent performance warrant fur-
ther investigation.
2.1.1 Passive Heat Maintenance Strategies
The use of specific methods (e.g. heated clothing, outdoor
survival jackets, and heating pads) which seek to attenuate
body temperature loss is known as passive heat mainte-
nance [28]. Such strategies are easily applied to the desired
muscle groups to maintain T
, and thus the temperature-
mediated pathways that aid performance [15]. For exam-
ple, repeated sprint performance and lower-body peak
power outputs were greater than observed in a control trial
when professional rugby union players wore a survival
garment during the post-warm-up recovery period [15].
Furthermore, the decline in lower-body peak power output
observed post-warm-up was significantly associated
(r=0.71) with the decline in T
In professional rugby union players who wore a survival
jacket during a simulated half-time period, muted losses of
(-0.74 ±0.08 % vs. -1.54 ±0.06 %) throughout
the 15-min period were observed versus a passive condition
[16]. The drop in T
over the simulated half-time was
significantly associated with reduced peak power output at
the start of subsequent exercise (r=0.63). In support of
previous authors [28,29], we proposed that the preserva-
tion of temperature-mediated pathways contributed to the
improved physical performances observed after the half-
time break.
Maintenance of T
during the half-time period is
therefore likely to attenuate decrements in subsequent
performance, especially during the initial stages of suc-
cessive exercise. Passive heat maintenance offers an
effective and practical method for preserving body tem-
perature, which helps to combat the decrements in per-
formance that may occur through the loss of T
However, further research into strategies that seek to
attenuate losses in body temperature and that have
application to team-sports players is warranted. Although
encouraging players to wear specific garments is recom-
mended and has proven beneficial [15,16,29], some
players (e.g. those receiving injury treatments) may find
this strategy restrictive when such clothing is worn during
half-time. Other methods of maintaining body temperature
during the half-time break should therefore be considered;
speculatively, the effects of increased changing-room
temperatures (within tolerable limits) may confer perfor-
mance advantages during subsequent exercise. However,
it is likely that modified hydration strategies are required
if such protocols are administered so that the potential
ergolytic effects resulting from impaired hydration status
are minimised.
2.1.2 Active Heat Maintenance Strategies (Half-Time Re-
Moderate-intensity running commencing after 7 min of a
half-time recovery period has been found to attenuate a
1.5 °C reduction in T
and protect the 2.4 % decrements in
mean sprint performance observed under passive control
conditions [6]. Moreover, the half-time decrease in T
correlated to the reduction in sprint performance observed
over half-time (r=0.60). Edholm et al. [5] reported sim-
ilar magnitudes of sprint performance maintenance and
attenuated losses in jump performance following a low-
intensity half-time re-warm-up. Additionally, intermittent
agility exercise, whole-body vibration, small-sided games
and lower-body resistance exercises performed during half-
time have been found to be beneficial [13,30].
Active re-warm-ups may also benefit skilled, as well as
physical, performances executed in the second half. For
example, 7 min of low-/moderate-intensity activity and
light calisthenics performed towards the end of half-time
improved performance during an actual match as less
defensive high-intensity running and more ball possession
was observed in the second half [5]. In support of the
findings of Edholm et al. [5], skilled performance during an
isolated technical assessment has also been reported to be
maintained when small-sided games incorporating skilled
actions are performed during a simulated half-time break
[30]. However, while active re-warm-ups appear beneficial,
consideration must be given to the duration of the activities
performed in the context of applied practice.
2.2 Post-Activation Potentiation
The ability of a muscle group to produce force can be
influenced by the previous contractive history of the same
muscle group [31]. The mechanisms of this transient
improvement in physical performance are suggested to
relate to enhanced motor neuron recruitment, a more
favourable central input to the motor neuron and/or an
enhanced Ca
sensitivity of actin–myosin myofilaments
[32]. Despite a large body of evidence supporting the
ergogenic effects of a preload stimulus [33], not all studies
have demonstrated performance improvements as a num-
ber of factors modulate the PAP response (e.g. the strength
of the participant, volume and type of the preload stimulus,
and the duration of recovery between the preload stimulus
and subsequent activity) [32]. When considering the
potential application of PAP during the half-time period of
team sports, the type of activities performed and the timing
of the preload stimulus are likely to be of primary interest.
M. Russell et al.
2.2.1 Timing between the Preload Stimulus
and Subsequent Activity
Improved physical performance attributable to PAP fol-
lowing a preload stimulus is a function of both muscle
fatigue and potentiation that simultaneously co-exist.
Optimised recovery between the preload stimulus and the
subsequent exercise therefore favours an acute enhance-
ment of subsequent performance as the effects of potenti-
ation persist for longer than the effects of fatigue [34].
Additionally, the time demands associated with established
half-time practices (Fig. 1) are likely to influence the
decision of whether to recommend performing a preload
stimulus to team-sports players.
Between 0 and 24 min has previously been reported to
separate the conditioning exercise and the subsequent
explosive activity. Power output, peak rate of force
development and countermovement jump height were
significantly elevated above baseline values at 8 min of
recovery for the majority (i.e. 70 %) of professional rugby
players who performed repeated assessments (i.e. baseline,
*15 s and every 4 min) of explosive activity in the 24 min
following a preload stimulus (i.e. three sets of three repe-
titions at 87 % 1-repetition maximum [1RM] squat) [31], a
finding that has since been confirmed [33]. From a practical
perspective, the transient nature of the PAP response means
that the benefit to performance may be limited to the initial
stages of a player’s involvement in subsequent competi-
tion. However, this is the period whereby decrements in
performance attributable to passive practices have been
shown to be at their greatest [16].
From studies where heavy-resistance exercise has been
used to induce PAP, explosive lower-body power produc-
tion is consistently compromised immediately after the
preload stimulus [33]. Therefore, should practitioners
consider the use of PAP during half-time, the preload
stimulus should be timed relative to the start of match-play
in order to minimise the effects that a transient reduction in
performance may have upon subsequent competition.
2.2.2 Type of Preload Stimulus Performed
Heavy (i.e. 75–95 % 1RM) resistance exercise has been
used as the preload stimulus in the majority of studies
examining the PAP phenomenon [33]. However, at half-
time this approach may not be feasible as issues relating to
access to facilities at away venues has previously been
reported [1]. Methods of stimulating PAP that have less
equipment demands and/or may be better tolerated by
players and coaches on the day of competition provide
attractive alternatives. Notably, ballistic activities such as
weighted jumps are associated with the preferential
recruitment of type 2 motor units [35], and may therefore
be utilised as a PAP stimulus. Furthermore, plyometric
exercise has also been found to potentiate sprint perfor-
mance [36].
Using jumps performed against a resistance of 2 % body
mass (via a weighted vest) that were incorporated into a
dynamic warm-up, improved jumping performance has
subsequently been observed in the following 2 min [37].
Similarly, Chen et al. [38] reported improvements in
countermovement jump height following multiple sets of
depth jumps. Turner et al. [36] recently reported that
*75 s of alternate-leg bounding performed with (?10 %
body mass) and without (body mass only) a weighted vest,
potentiated subsequent sprint performance when compared
with a control trial. Notably, a greater enhancement of
sprint performance was observed in the body mass plus
10 % trial when compared with the body mass only trial,
and this increase was related to the baseline speed of
Practitioners may therefore wish to recommend plyo-
metric activities during the final stages of half-time to
enhance subsequent performance. Notably, the shorter
durations of PAP-inducing exercise are likely to be better
tolerated when compared with those typically used in
active re-warm-up studies (*7 min). However, consider-
ation should also be given to the fact that a transient
reduction in performance is commonly observed in the
immediate period (i.e. \3 min) following the preload
stimulus [33] and that the effects of PAP as a specific half-
time strategy have not been directly examined.
2.3 Hormonal Priming
High-intensity exercise can promote rapid changes in the
hormonal milieu postulated to benefit subsequent exercise
performance [39,40]. Indeed, in a workout performed
2 min after a short-duration (*40 s) maximal exercise
bout that elevated salivary testosterone concentrations,
improved strength performance was observed in profes-
sional rugby players [40]. Acute modification of the hor-
monal environment induced by the bout of sprint-cycle
exercise was reported to have contributed to the improve-
ment of subsequent exercise performance [40]. In support
of this finding, previous authors have observed improved
upper-body strength profiles following the systemic ele-
vation of endogenous hormones via prior lower-body
resistance exercise [41].
Interestingly, a number of authors have also reported
that the content of videos watched prior to exercise can
influence hormonal responses and subsequent physical
performance. For example, in professional rugby players,
Cook and Crewther [42] observed improvements in squat
strength 15 min after watching short (4 min) video clips
that included aggressive, training, erotic or humorous
Half-Time Strategies in Team Sports
content. Notably, the aggressive video caused significant
increases in salivary testosterone that exceeded all other
video types and improved squat performance more so than
either the erotic or humorous clips. Moreover, viewing
footage 75 min before a match that showed successful skill
executions performed by an athlete, which was reinforced
with positive coach feedback, promoted the highest pre-
game testosterone concentrations and best subsequent
performance ratings [43]. Conversely, presenting footage
of successful skill executions of opposing players while
providing cautionary coach feedback, induced an enhanced
stress response [43].
While the direct effect of specific hormonal priming
strategies administered during the half-time break have not
yet been examined, and assuming that the relationships
between pre-match testosterone concentrations and match
performance [44] remain true, it is plausible that strategies
which elevate free testosterone employed during the half-
time break may improve subsequent match performance.
As shown in Fig. 1, half-time often includes a period of
tactical instruction, be it either individual or team-based,
which may utilise video playback [1]. Therefore, modifi-
cation of the footage and feedback presented to the players
may offer a simple strategy to improve subsequent per-
formance. Furthermore, high-intensity exercise, perhaps
used as part of a half-time re-warm-up, may also optimise
the hormonal milieu that contributes to improved exercise
performance thereafter.
2.4 Carbohydrate Consumption
When soccer has been used as the modality of exercise,
numerous authors have reported that muscle glycogen
concentrations reduce throughout both simulated and
actual match-play [45,46]. Consequently, team-sports
players are often encouraged to acutely consume carbo-
hydrates on the day of competition. Such recommendations
usually include guidance to ingest carbohydrates in the
hours before exercise, throughout competition and during
breaks in play, such as at half-time [47]. The proposed
mechanisms of ingesting carbohydrates relate to an effort
to spare muscle glycogen and to maintain blood glucose
concentrations for the duration of a match [4850]. How-
ever, the physiological response to carbohydrates con-
sumed during exercise, such as a match, differs to that
observed when carbohydrates are consumed in the non-
exercising state [51], similar to half-time.
Under normal physiological conditions, ingesting car-
bohydrates that increase blood glucose concentrations in a
passive state elicits an increase in insulin synthesis and
secretion from the bcells of the islets of Langerhans.
Insulin, in an attempt to normalize blood glucose concen-
trations, subsequently decreases lipolysis and increases
glucose uptake in liver, skeletal muscle and fat cells [51].
Conversely, hyperglycaemic responses are observed during
high-intensity exercise by the actions of counter-regulatory
hormones, including catecholamines, cortisol and growth
hormone [51]. Given the pattern of competitive match-play
in team-sports competition, it is surprising that the influ-
ence of carbohydrate supplementation on the glycaemic
response to a bout of exercise that is completed after a
period of recovery from a previous bout of exercise has
received little attention.
Ingestion of a 6 % sucrose-electrolyte beverage before
(i.e. within 2 h of commencing exercise and within 5 min
of starting each half) and during (i.e. every 15 min of
exercise) simulated soccer-specific exercise attenuated a
reduction in post-exercise shooting performance (assessed
during an isolated soccer skills test) [19]. However, in
support of data reported by Bangsbo et al. [52], exogenous
carbohydrate provision before and during soccer-specific
exercise reduced blood glucose concentrations during the
initial stages of the second half by *30 %, a finding that
has since been confirmed in both simulated and actual
soccer match-play [18,20]. Most likely, this exercise-
induced rebound glycaemic response is explained by the
previously active muscles increasing glucose uptake, low-
ered catecholamine concentrations, and reduced stimula-
tion of liver glycogenolysis at the start of the second half
It appears that cerebral glucose availability is
impaired when blood glucose concentrations fall below
3.6 mmolL
[53], and cognitive performance decre-
ments occur when blood glucose concentrations fall
below 3.4 mmolL
[5463], concentrations that rep-
resent those previously reported in soccer players [20,
64]. As the quality of cognitive and physical perfor-
mances executed during and after soccer-specific exer-
cise appear to be influenced by changes in blood
glucose concentrations, strategies that maintain glyca-
emia for the full duration of match-play represent an
opportunity to achieve maximum soccer performance. A
number of factors, including the glycaemic index of the
carbohydrate consumed, timing of consumption and the
dose consumed, are likely to modulate the efficacy of
carbohydrates consumed on the day of competition [65].
In this review we present an overview of studies that
have application to these factors in the context of the
half-time break.
2.4.1 Glycaemic Index
Commercially-available sports drinks generally tend to
consist of between 6 and 10 % concentrations of high-
glycaemic index carbohydrates (e.g. maltodextrin).
Ingesting high-glycaemic index carbohydrates while in a
M. Russell et al.
non-exercising state, such as that observed during the ini-
tial phases of half-time, results in rapid increases in post-
prandial blood glucose concentrations. However,
consumption of high-glycaemic index carbohydrates in the
hour before exercise has also been reported to lower blood
glucose concentrations 15–30 min after starting subsequent
activity [55,66], a response attributed to free fatty acid
inhibition which increases carbohydrate usage throughout
isolated exercise bouts performed soon after carbohydrate
ingestion [55].
As highlighted in Sect. 2.4, we have consistently
reported that consuming sucrose-electrolyte beverages
before, and throughout, simulated soccer match-play
caused transient reductions in blood glucose concentrations
in the initial stages of the second half of soccer-specific
exercise [19,20,67]. However, low glycaemic index car-
bohydrates prolong the delivery of glucose to the systemic
circulation. Indeed, mean and peak oxidation rates of iso-
maltulose have been reported to be 50 and 42 % lower than
the oxidation rates of sucrose, respectively, when ingested
at the same rate (1.1 gmin
)[68]. Although the effects of
different glycaemic index carbohydrates consumed during
the half-time period remain to be examined, it is plausible
that a reduced rate of digestion and absorption of low-
glycaemic index carbohydrates prolongs blood glucose
concentrations that have typically been found to decline in
the second half of intermittent activity.
2.4.2 Timing of Ingestion
Consistent evidence provided from studies requiring that
carbohydrates are consumed before a single bout of exer-
cise demonstrate that the timing of pre-exercise carbohy-
drate ingestion can influence subsequent metabolic
responses. For example, Moseley et al. [69] investigated
the metabolic response to 75 g of glucose ingested 15, 45
or 75 min before exercise. Plasma glucose and insulin
concentrations were significantly elevated immediately
before exercise in the 15-min feeding group, whereas the
lowest insulin concentrations were observed when carbo-
hydrate was ingested 75 min before exercise. Similarly,
ingestion of a 20 % fructose solution 15 min before the
second half of an intermittent cycling protocol resulted in
reductions in blood glucose concentrations compared with
pre half-time values for 40 min of the second half [24].
Consequently, the timing of carbohydrate ingestion during
the half-time period has the potential to influence respon-
ses; however, no studies have systematically examined the
influence of modifying the timing of carbohydrates pro-
vided during half-time in soccer players.
2.4.3 Dose Consumed
In studies that have employed continuous exercise proto-
cols and have focused on water absorption as a priority, the
detrimental effects observed on gastric emptying and
intestinal absorption have led to recommendations that
beverages containing between 5 and 8 % carbohydrates are
consumed during exercise [68,70,71]. However, when
intermittent exercise is performed, limited data currently
exist about the effects of providing additional carbohy-
drates (9 % solutions). Notably, ingestion of a 20 % glu-
cose solution has been reported to enhance sprint capacity
after 90 min of intermittent cycling [24], and a dose-
dependent relationship exists between the amount of car-
bohydrate consumed and indices of cognitive function in
non-exercising participants [72].
In recreational soccer players, greater blood glucose
concentrations have been observed from 75 min onwards
relative to a fluid–electrolyte placebo when a 9.6 % car-
bohydrate–electrolyte beverage was consumed before and
during (including at half-time) a simulated soccer match
[18]. Interestingly, differences in glycaemic responses were
observed despite similarities in blood glucose concentra-
tions between conditions at the 60 min time point
(*4.0 mmolL
). As the pre-exercise carbohydrate dos-
age appears to elicit similar glycaemic responses [68,73],
and that the rebound hypoglycaemic response appears to
decay within the initial stages of exercise when high-gly-
caemic index carbohydrates are consumed [24,69], it is
plausible that provision of additional carbohydrates at half-
time may afford ergogenic effects in the latter stages of a
match; however, this remains to be confirmed.
2.4.4 Interactions between Carbohydrate Ingestion
and a Half-Time Re-Warm-Up
It is well established that high-intensity exercise can elicit a
hyperglycaemic response in both clinical and non-clinical
populations. An exercise-induced catecholamine release
inhibits pancreatic b-cell activity [74]; therefore, elevated
blood glucose concentrations result from exogenous car-
bohydrate provision during exercise. It is therefore plau-
sible that a combination of high-intensity exercise
performed during the half-time period, as well as simul-
taneous carbohydrate ingestion, could feasibly maintain
blood glucose concentrations thereafter. In support of this,
Achten et al. [68] observed that ingestion of 600 ml of a
concentrated maltodextrin drink consumed during a 25-min
cycle warm-up that included isolated sprint bouts,
increased catecholamine concentrations, blunted the insulin
Half-Time Strategies in Team Sports
response and actually increased blood glucose concentra-
tions at the onset of exercise. Although reductions in blood
glucose concentrations were observed after 20 min of
subsequent continuous exercise, these differences were
non-significant. Consequently, a half-time re-warm-up that
includes a high-intensity component, combined with the
ingestion of carbohydrates, may prove beneficial for team-
sports players who experience an exercise-induced rebound
glycaemic response. However, this is yet to be determined
when carbohydrates are provided during recovery from
previous activity and when the exercise performed is
intermittent in nature.
2.4.5 Carbohydrate Mouth Rinsing
Mouth-rinsing carbohydrate solutions can positively influ-
ence the perception of effort during subsequent exercise
and facilitate peak power output during the initial stages of
repeated sprint tests [75,76]. The mechanisms proposed
relate to the excitation of reward and motor control centres
in the brain [77] and an enhanced corticomotor pathway
excitability [78] induced by oral receptor stimulation.
Whether the presence of carbohydrate in the mouth can
facilitate improvements in subsequent performance when
used as a half-time strategy remains to be investigated;
however, the benefits of mouth swilling observed during
exercise provide a rationale for using this strategy at half-
2.5 Caffeine Consumption
The ergogenic effects of caffeine (a central nervous system
stimulant) in team-sport athletes have been proposed to
relate to the attenuation of fatigue-related decrements in
skilled performances, concentration or cognitive function
as opposed to enhanced endurance capacity [79]. With
respect to soccer skill performance, the efficacy of caffeine
is unclear [65] despite the mean sprinting performances of
recreational players being improved when doses of
body mass were co-ingested with
142 ±3gh
of carbohydrate [18]. Additionally, the
mean performance of rugby passes made during an isolated
technical test over the duration of a simulated match was
improved when caffeine was ingested [80]. Therefore,
caffeine consumed during half-time may be efficacious for
subsequent performance.
When considering whether to recommend caffeine use
during half-time, the time-course of peak systemic con-
centrations of caffeine and/or its metabolites following
acute ingestion is likely to be of interest to practitioners.
Whether caffeine is consumed in either the fed or fasted
state appears to influence the rate of subsequent appearance
in the circulation [71]. Nevertheless, when the mechanisms
of action are reliant upon absorption via the lower gastro-
intestinal tract, peak concentrations of caffeine and/or its
metabolites are generally realised within 1 and 3 h of
ingestion. However, the efficacy of drug administration has
been proposed to be related to its speed of absorption [81]
and the ergogenic effects of caffeine have also been
attributed to the antagonism of receptors in the upper
gastrointestinal tract facilitating a central modulation of
motor unit activity and adenosine receptor stimulation [82].
In the last decade, caffeinated chewing gums have
become commercially available and have been associated
with significantly faster absorption times when compared
with a traditional pill-based administration modality [83].
For example, Ryan et al. [81] have recently observed
improved cycling performance when caffeinated gum
containing 300 mg of caffeine was provided 5 min before
exercise. Interestingly, providing the same dose of caffei-
nated gum 60 and 120 min prior to the start of exercise
negated the ergogenic effects observed. Despite very few
studies having investigated the effects of this novel method
of caffeine delivery, early evidence suggests that caffei-
nated gum may benefit the performance of intermittent
team-sports players. Furthermore, the time-course of
effects of action of caffeinated gums mean that they could
plausibly be consumed during half-time.
3 Model of Theoretical Application
As reviewed, the transition from a period of exercise to rest
and back to exercise replicates the general demands of a
number of team sports. This pattern of activity induces a
number of physiological effects that appear to influence
performance during subsequent exercise. Notably,
impaired performance has been observed during the initial
stages of the second half. Therefore, when seeking to
optimise performance throughout the full duration of
competition, half-time is an opportunity to employ specific
strategies that seek to maintain performance throughout the
second half.
However, the match-day practices of professional teams
are often very structured and rigid in nature. It is therefore
important that any proposed modification to the half-time
period seeks to complement, rather than replace, existing
protocols. Therefore, practical recommendations concern-
ing the implementation of such strategies may be beneficial
for the sports scientist and/or strength and conditioning
coach. In this review we present a theoretical model of
organising a 15-min half-time period to incorporate both
the practices currently employed and the strategies that we
have proposed to acutely enhance performance (Fig. 2).
While this proposed theoretical model may appear quite
complex, applied practitioners are encouraged to interpret
M. Russell et al.
our recommendations within the context of the require-
ments of their specific sports. Speculatively, these recom-
mendations may also have application outside of the
context of the half-time break as some sports (e.g. rugby
league) allow rolling interchanges and therefore players
may experience extended breaks in play between consec-
utive match involvements.
In order to attenuate the losses in body temperature
observed during the half-time break, strategies that seek to
maintain temperature-mediated pathways [15] should be
considered. Heated clothing, outdoor survival jackets and
heating pads can be applied with relatively little inconve-
nience to athletes, and have proved beneficial when seeking
to attenuate reductions in performance attributable to T
loss [15,16,29]. Furthermore, an increased changing-room
temperature may also prove worthwhile; however, this
remains to be explored.
At some point throughout half-time, individualised
footage of successful player skill executions supported by
affirmative positive cues from a coach may also benefit a
player’s subsequent performance [43]. However, it should
be noted that if such videos focus upon the successful skill
executions of opposing players while cautionary coach
feedback is provided, an enhanced stress response can be
observed [43]. Furthermore, acute bouts of high-intensity
exercise may prove beneficial in terms of priming the sys-
temic hormonal environment for subsequent exercise [40].
Active re-warm-ups administered in the final stages of
half-time improve subsequent physical and technical per-
formance by attenuation of the reductions in body tem-
perature seen when passive half-time practices are
performed [5,6,13,14]. As PAP has been observed fol-
lowing short-duration plyometric activities [36], such
exercises, when used as part of a re-warm-up strategy, may
serve as a time-efficient method of improving subsequent
Due to the mechanisms of action, the presence of caf-
feine and carbohydrate in the mouth has been found to
facilitate motor output and improve subsequent exercise
[76,81]. However, based upon literature examining the
efficacy of caffeine, if the duration between ingestion and
subsequent exercise is prolonged, the ergogenic effects of
these substances can be lost [81]. Therefore, within the
final stages preceding the restart of competition, the pro-
vision of caffeinated gum (with subsequent expectoration
before competition recommences) and carbohydrate solu-
tions (for the purposes of mouth swilling) should be con-
sidered (Fig. 2).
Finally, when seeking to minimise perturbations in
blood glucose concentrations that have consistently been
observed when recommencing the second half of exercise,
it is plausible that half-time strategies relating to the con-
sumption of exogenous energy (i.e. carbohydrates) could
be optimised by modifying the glycaemic index of the
beverage consumed, the timing of ingestion, the amount of
carbohydrate consumed and/or by combining ingestion
with a half-time re-warm-up. Therefore, consideration of
these factors should be given, especially in players deemed
to be susceptible to reduced blood glucose concentrations
upon restarting exercise.
Fig. 2 Theoretical model of strategies suggested during a 15-min half-time period
Half-Time Strategies in Team Sports
4 Conclusion
Periods of reduced activity between successive exercise
bouts have been found to influence an array of physio-
logical responses. Furthermore, reduced physical and
cognitive performance, as well as increased risk of injury,
have been identified in the initial stages of the second half
of team-sport competition. Therefore, the support of pre-
vious authors for the use of heat maintenance strategies,
half-time re-warm-ups (including actions to induce PAP),
hormonal priming, and caffeine and carbohydrate con-
sumption means that a method which combines a number
of these strategies for use on the day of competition may be
of interest to sports scientists and strength and conditioning
coaches involved with team sports. In addition to
appraising the evidence of these isolated strategies, we
have presented a practical model that allows combination
of a number of interventions that could theoretically elicit
additive effects over the use of such strategies in isolation.
However, given the differences that exist between sports in
half-time regulations (e.g. duration of break, access to
pitch, etc.), and players’ normal practices, we recommend
that the model is interpreted with considerable flexibility,
and we acknowledge that some adjustment is likely
dependent upon the players involved.
Acknowledgments No sources of funding were used to assist in the
preparation of this review. The authors have no potential conflicts of
interest that are directly relevant to the content of this review.
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M. Russell et al.
... SMFR is used to prevent injuries and maintain performance in sports [136,137]. For example, in soccer, in the early period after half-time, both physical and cognitive performance is reduced, and the risk of injury increases [138]. Kaya et al. tested the effects of SMFR by replicating the running distance and half-time experienced during a game with soccer players of various levels [139]. ...
... When the fascia is restricted in any part, it causes stress and impairment in other areas [156], depending on the continuity of the myofascial structure, and reduces muscle flexibility [138]. This is a particularly important issue for athletes subjected to long-term repetitive strain, and using SMFR with FR is an important part of an athlete's training. ...
... This is a particularly important issue for athletes subjected to long-term repetitive strain, and using SMFR with FR is an important part of an athlete's training. Therefore, SMFR with FR is recommended for inclusion in athletes' training regarding performance loss, injury prevention, and recovery [138]. ...
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Damage to the fascia can cause significant performance deficits in high-performance sports and recreational exercise and may contribute to the development of musculoskeletal disorders and persistent potential pain. The fascia is widely distributed from head to toe, encompassing muscles, bones, blood vessels, nerves, and internal organs and comprising various layers of different depths, indicating the complexity of its pathogenesis. It is a connective tissue composed of irregularly arranged collagen fibers, distinctly different from the regularly arranged collagen fibers found in tendons, ligaments, or periosteum, and mechanical changes in the fascia (stiffness or tension) can produce changes in its connective tissue that can cause pain. While these mechanical changes induce inflammation associated with mechanical loading, they are also affected by biochemical influences such as aging, sex hormones, and obesity. Therefore, this paper will review the current state of knowledge on the molecular level response to the mechanical properties of the fascia and its response to other physiological challenges, including mechanical changes, innervation, injury, and aging; imaging techniques available to study the fascial system; and therapeutic interventions targeting fascial tissue in sports medicine. This article aims to summarize contemporary views.
... There is a positive performance correlation between a sport and the specificity of the warm-up processes (34). Similarly, a common theme exists relating to the effectiveness of PAPE-how closely the conditioning activity relates to the subsequent task (32). ...
... Studies that compared a vertical movement or horizontal movement to a similar outcome measurement had an effect size 5 0.35, whereas using an intervention different to the outcome measurement had an effect size 5 0.19, and although not significantly different from each other, the similar subgroup had a significant benefit compared with the control group, whereas the different subgroup did not. This has been reiterated in previous studies investigating the effects of PAPE, athlete preparation, and warm-up optimization (9,34,46). ...
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Brink, NJ, Constantinou, D, and Torres, G. Postactivation performance enhancement in healthy adults using a bodyweight conditioning activity: a systematic review and meta-analysis. J Strength Cond Res XX(X): 000-000, 2022-A systematic review and meta-analysis were conducted to review the available evidence on whether a bodyweight conditioning activity can acutely improve the performance outcome of a subsequent task through postactivation performance enhancement. Data sources included PubMed (National Library of Medicine), Web of Science (Clarivate Analytics), Google Scholar, SPORTDiscuss (EBSCO), Embase (Elsevier), and Thesis Global. Subjects were healthy, active adults who performed either a vertical jump or a linear sprint outcome measurement. All studies were randomized controlled trials where the effects of a bodyweight conditioning activity were compared with a control condition. The control group followed the same course as the experimental group excluding the intervention, with the intervention and outcome measurement carried out in the same session. The intervention was completed before the initiation of the outcome measure testing. Nineteen studies fulfilled the eligibility criteria and were included. There was a small overall effect of 0.30 (95% confidence interval 0.14-0.46, p = 0.0003) in favor of using a bodyweight conditioning activity to improve the outcome of a subsequent vertical jump or linear sprint. Secondary analysis indicated that there was no difference between the vertical jump and sprint subgroup, <5 minutes or 5 minutes and greater between the intervention and outcome measurement subgroup, or whether an intervention with the same movements or different movements was used before the outcome task subgroup. Using bodyweight conditioning activities before performing a maximal vertical jump or sprint may provide a small benefit in performance outcome.
... Each sport or athletic competition involves its own circumstances that determine per-cooling method practicality (Russell et al., 2015), for example, in rugby sevens, only short breaks (i.e. ~2 min at halftime) provide the only planned opportunity for cooling strategies to be implemented. ...
... Accordingly, the demonstrated blunting of T Tymp during COOLING may account for the increased power output seen during the timetrial in the current study, due to preservation of maximal voluntary contraction and voluntary activation (Minett et al., 2011). Taken together, it seems that aggressive short-duration mixed-method half-time cooling strategies, which fit within the practical limits of the break interval, may be the most effective for physiological, perceptual, and performance benefits (Russell et al., 2015). ...
Purpose: The ingestion of ice slurry and application of ice towels can elicit favorable physiological, perceptual, and performance benefits when used individually; however, the combined use and effectiveness of these practical cooling strategies have not been assessed using a sport-specific performance test, based on actual match demands, in an elite team sport context. Methods: Ten non-heat acclimated elite male rugby sevens athletes undertook two cycling heat response tests (HRT) designed to be specific to the demands of rugby sevens in hot conditions (35°C, 80% rH). In a crossover design, the HRTs were conducted with (COOLING) and without (HOT) the combined use of internal (ice slushy ingestion) and external (application of ice towels to the head, neck, and face) pre- and per-cooling strategies. Physiological, perceptual, and performance variables were monitored throughout each HRT. Results: COOLING resulted in reductions in mean tympanic temperature (−0.4 ± 0.2°C; d = 1.18); mean heart rate (−5 ± 8 bpm; d = 0.53); thermal discomfort (−0.5 ± 0.9 AU; d = 0.48); and thirst sensation (−1.0 ± 1.1 AU; d = 0.61) during the HRT. COOLING also resulted in a small increase in 4-min time trial power output (by 7 ± 33 W, ~3%; d = 0.35) compared to HOT. Discussion: A combination of internal and external pre- and per-cooling strategies can result in a range of small physiological, perceptual, and performance benefits during a rugby sevens specific HRT, compared to undertaking no cooling. Practitioners should include such strategies when performing in hot conditions.
... In football, it has also been shown that a 12-minute inactive period after a traditional warm-up resulted in impaired physical performance of the players (1). These performance decrements can be also observed after passive half-time breaks (30), which supports the idea that inactivity periods may be suboptimal for subsequent performance (41). This phenomenon may be theoretically explained by decreases in muscle temperature or muscle activation that may compromise acute neuromuscular performance (9), reinforcing the need to consider supplementary conditioning activities during traditional warm-up routines. ...
Abade, E, Brito, J, Gonçalves, B, Saura, L, Coutinho, D, and Sampaio, J. Using deadlifts as a postactivation performance enhancement strategy in warm-ups in football. J Strength Cond Res XX(X): 000-000, 2022-Postactivation performance enhancement activities may be relevant warm-up strategies aiming to improve subsequent physical performance. The purpose of the current study was to investigate the effects of adding barbell deadlift or hex-bar deadlift exercises to current warm-up routines on running and jumping performances in football players. Ten highly trained male football players participated in the study during the competitive phase of the season. All players performed 3 protocols in the same week: a standard warm-up that included players' regular routines and 2 other protocols with the addition of barbell or hex-bar deadlift, after the end of the warm-up (3 sets of 3 reps, progressing set by set from 60% to 85% repetition maximum). All protocols had the same time interval between pretest (immediately after the warm-up) and posttest (15 minutes after the warm-up). Vertical jumping (countermovement jump [CMJ]; Abalakov jump [AJ]) and running performances (505 test) were impaired 15 minutes after the standard warm-up (CMJ: -6.7 ± 4.2%; AJ: -8.1 ± 8.4%; and 505 time: 1.4 ± 2.5%). For warm-up with the addition of barbell deadlift, vertical jump increased by 4.3 ± 5.6% (Cohen's dunb: 0.23 [0.02-0.47]) and 505 time decreased by -5.9 ± 3.6% (Cohen's dunb: 0.97 [-1.68 to -0.43]). The warm-up with hex-bar deadlift led to trivial changes for CMJ and AJ, but 505 time decrease by -2.7 ± 2.6% (Cohen's dunb: -0.53 [-1.01 to -0.13]). The deadlift exercise can be added to warm-up routines to maintain or even enhance acute physical performance. However, coaches and practitioners should be aware that performance enhancements resultant from deadlift may vary according to individual physical profiles.
... Similarly, Crowley et al. (1991) found the decrement in physical performance to be ~4% per 1°C after muscle cooling. Considering that temperature rapidly decreases during periods of inactivity (Galazoulas et al., 2012), researchers have recently been interested in investigating strategies to prevent this decline in competitive matches, especially during half-time (HT) (Russell et al., 2015). Therefore, there is a growing public and scientific interest in addressing the effects of performing re-warm-up (RW-U) activities (González-Devesa et al., 2021). ...
Re-warm-up activities are recommended in team sports due to loss of muscle temperature during half-time. This study aimed to evaluate the effects of a half-time re-warm-up strategy on female basketball players. Ten players U14, separated into two teams of five players, performed either a passive rest condition or repeated sprints (5×14 m) plus 2 min of a shooting wheel (re-warm-up condition), during the half-time break (10 min) of a simulated basketball match, where only the first three quarters were played. The re-warm-up did not elicit significant effects on jump performance and locomotory responses during the match, except for the distance covered at a very light speed, which was significantly higher than in the passive rest condition (1767 ± 206 vs 1529 ± 142 m; p < 0.05). Mean heart rate (74 ± 4 vs 70 ± 5%) and rate of perceived exertion (4.5 ± 1.5 vs 3.1 ± 1.44 a.u.) were higher in the re-warm-up condition during half-time (p < 0.05). In conclusion, performing re-warm-up activities based on sprints could be a valuable strategy to avoid the reduction of sport performance during prolonged breaks, but given the limitations of the study, these relationships need to be further explored in official competitions.
... In this regard, Crowley et al. (1991) found the decrement in physical performance to be in the order of ~4% per 1°C after muscle cooling. For this reason, it has been suggested that passive rest may not be beneficial to performance during this recovery period (Russell et al., 2015).Previous studies have suggested performing an active warm-up (RW-U) during the half-time (HT) period (Silva et al., 2018). Different investigations performed in intermittent team sports showed that performing RW-U methods based on cycling (R. J. Lovell et al., 2007) and strength or sport-specific exercises (Zois et al., 2013) could be beneficial for improving performance in the second half. ...
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Problem Statement: Passive rest during basketball games could reduce athletes' performance and increase the risk of injury during the second half of the game due to loss of muscle temperature. Approach: The re-warm-up activities during half-time could help avoid this problem, but there is a lack of research on their efficacy, especially in basketball. Purpose: This study aimed to assess the influence of two half-time re-warm-up strategies (that do not demand additional equipment) on measures of performance and the physical, sports and perceptual response during a basketball simulated match. Methods: Ten female basketball players U16 completed a traditional intervention and alternative strategy based on bouncing, in which participants completed two 40-minute games (4 x 10-minute periods with a 10-minute half-time interspersing the third and fourth periods) separated by four days. The traditional trial comprised a passive 6-minute period followed by 3 minutes of shooting wheel, whilst the alternative trial comprised a passive 6-minute period, followed by 1 minute of bouncing and 2 minutes of shooting wheel. The re-warm-up protocols were completed 1 minute before the beginning of the second half. Results: The re-warm-up did not show significant effects on jump performance and rating of perceived exertion immediately after half-time and after the second half of the basketball simulated match. No significant changes were identified for heart rate and locomotory responses during the game, except for the distance covered at a very light speed which was significantly higher in the traditional group. Conclusions: These data support that adding a bouncing exercise to a classic re-warm-up during half-time does not lead to additional improvement in young female basketball players.
... Finally, for match or competition days, intakes of 1-4 g/kg of easily digestible CHO 2-4 h prior to the event may be recommended [15,84,89]; half-time intakes of small amounts of easily absorbable CHO of 30-60 g/h or even mouth rinses may be sufficient to replenish glycogen stores and maintain blood glucose levels during the second half [89,90]; and intakes of 1. 2 g CHO/kg including CHO-dense foods and beverages for 2 h post-match are recommended to take advantage of enhanced glycogen repletion rates, especially when the recovery period between matches is short [15,36,84,91]. ...
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Introduction: Modern handball was introduced as an Olympic sport in 1972 and is played by more than 19 million people worldwide. Beach handball was born as an adaptation of court handball in the 1990s. Both modalities are complex and multifactorial ball games characterised by a fast pace and variable game intensities, as well as the strong influence of tactical concepts, social factors and cognitive aspects. Objective: To analyse the nutritional status of both male and female players to assess whether it is in line with specific and general dietary intake demands. Methodology: A systematic search of databases was carried out using keywords with relevant Boolean operators. Results: A total of 468 studies was identified, of which 44 studies were included: 7 on hydration; 22 studies related to energy, macronutrient and fibre intake; 23 that assessed micronutrients; 4 studies on nutritional knowledge and information sources; and 2 articles on eating disorders. A further 85 articles were included in order to cross-check results. Discussion: The need for a state of euhydration and normal plasma electrolyte levels is clear. Adequate energy intake is the cornerstone of the handball athlete’s diet to support optimal body function. The ACSM sets daily recommendations of 6–10 g CHO/kg body weight for handball, and daily protein recommendations range from 1.2 to 2.0 g PRO/kg/day and 14 g dietary fibre per 1000 kcal. Conclusion: The nutritional habits of handball players do not seem to be adequate to the demands of the sport, although these demands are not clarified. The inclusion of nutrition professionals could be a key element in the performance of these athletes.
... Mouchet and Maso (2018) highlighted the delivery of messages and strategy formation as key components of elite rugby HTs. Similarly, Russell, West, Harper, Cook, & Kilduff, (2014) noted a strong emphasis on relaxation and recovery and receiving tactical information in elite soccer HTs. This study highlights the prominent role that coaches play in facilitating crucial HT components. ...
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Half-time (HT) is an important component of a coach’s performance strategy. Qualitative investigations of HTs within elite rugby are conspicuous by their absence in the exigent research. The aim of this study was to critically evaluate coach and player experiences of HTs in elite rugby union, and to identify effective HT strategies. This study utilised a qualitative descriptive approach, adopting an interpretivist paradigm. A purposeful sample of 16 participants (8 coaches, 8 players) engaged in a semi-structured interview. Data was subjected to thematic analysis. The creation of a calm environment, facilitated by an emotionally controlled coach, was a prerequisite to effective HTs. Player recovery and the provision of a succinct tactical and technical plan for the 2nd half, devised through a collaborative approach were also prioritised by the participants. In conclusion, participants believed that when “done well”, HT offered an important window in which to positively impact 2nd half performance.
... The concurrent supplementation (SUP) of CAF and CHO before or during exercise has produced inconsistent results (Guest et al. 2021). Firstly, simultaneous CAF and CHO SUP has been shown to improve performance during predominantly aerobic, endurance and intermittent exercises due to the ability to maintain glycogen stores and blood glucose levels while decreasing values of rating of perceived exertion (RPE) (Russell et al. 2015;Conger et al. 2011). Moreover, CAF SUP when combined with CHO could improve energy availability (Kerksick et al. 2018), cognitive performance (Bernard, Louise, and Louise 2018), intestinal glucose absorption and rate of exogenous CHO oxidation (Van Nieuwenhoven, Brummer, and Brouns 2000;Yeo et al. 2005). ...
Carbohydrates (CHO) and caffeine (CAF) are two ergogenic aids commonly used among athletes to enhance performance. However, there is some controversy as to whether the concurrent intake of both supplements might result in an additive and synergistic improvement in exercise performance. The aim of this systematic review and meta-analysis was to determine the effect of adding CAF to a protocol of CHO ingestion, compared with the intake of each ergogenic aid alone and with placebo, on exercise performance and metabolic responses in healthy young physically active adults. This study was conducted according to PRISMA 2020 guidelines. The PubMed, Web of Science, Medline Complete, CINAHL, SPORTDiscus and CENTRAL databases were searched including randomized controlled trials (RCT) that were at least single blind. The risk of bias assessment was performed using the Cochrane Risk-of-Bias tool 2. Meta-analysis were performed on performance variables and rating of perceived exertion (RPE) using the random-effects model. Thirteen RCT with 128 participants (117 men and 11 women) were included in this study. The ingestion of CAF and CHO reduced sprint time during repeated sprint protocols in comparison with CHO isolated ingestion (SMD: −0.45; 95% CI: −0.85, −0.05) while there was a tendency for a reduction in the time employed during time trials (SMD: −0.36; 95% CI: −0.77, 0.05). The RPE tended to be lower with CAF and CHO compared with CHO isolated ingestion during steady-state exercise (SMD: −0.43; 95% CI: −0.91, 0.05) with no differences between conditions in performance trials (SMD: −0.05, 95% CI: −0.39, 0.29). Although most of the studies showed higher values of blood glucose when CHO was co-ingested with CAF compared with PLA, only two studies observed higher values with CHO and CAF co-ingestion with respect to the isolated intake of CHO. One study observed greater fat oxidation and lower glycogen use when CAF was added to CHO. In terms of cortisol levels, one study showed an increase in cortisol levels when CAF was co-ingested with CHO compared with PLA. In summary, concurrent CHO and CAF intake may produce an additive ergogenic effect respect of the isolated ingestion of CHO. This additive effect was present when CHO was provided by a 6–9% of CHO solution (maltodextrin/dextrin + fructose) and CAF is administered in a dose of 4–6.5 mg/kg.
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O objetivo do presente estudo foi avaliar os efeitos do exercício prévio específico sobre o desempenho em teste intermitente de alta intensidade em jogadoras de futsal e variáveis associadas. Para isso 13 jogadoras amadoras de futsal (24,1 anos; 63,6 kg; 1,61 m; IMC = 24,3 kg/m2; % de gordura = 27,9), de maneira cruzada, passaram por duas sessões experimentais separadas por sete dias. Em uma das sessões era realizado um exercício prévio (EP): três primeiros níveis do Yo Yo intermittent recovery test level 1 (YYIR1) repetidos por três vezes. Na sessão controle (CON), as jogadoras permaneciam em repouso (5 min) e após, em ambas as sessões, era realizado o YYIR1 até a exaustão. Antes do início da sessão eram reportadas escalas de recuperação e dor muscular de início tardio, a frequência cardíaca (FC) foi monitorada por toda sessão e, ao término, a percepção de esforço (PSE) era registrada. As percepções de recuperação (p = 0,23) e de dor (p = 0,36) não diferiram entre as sessões EP vs. CON. A FC média durante o exercício prévio foi de 111,3 ± 7,7 bpm. A distância percorrida no YYIR1 não diferiu (p = 0,25) também entre EP (372,3 ± 103,8 m) vs. CON (341,5 ± 84,2 m), bem como a monitoração da FC (mínima, média e máxima). Entretanto, a PSE foi menor (p = 0,0008) na sessão EP (8,5 ± 0,7 UA) do que em CON (9,3 ± 0,6 UA). Assim, concluímos que o exercício prévio não influencia o desempenho intermitente de alta intensidade (YYIR1), nem as variáveis de FC. Porém, o exercício prévio gera menores níveis de percepção de esforço (intensidade interna) em comparação ao repouso antes do YYIR1.
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Despite limited scientific evidence supporting their effectiveness, warm-up routines prior to exercise are a well-accepted practice. The majority of the effects of warm up have been attributed to temperature-related mechanisms (e.g. decreased stiffness, increased nerve-conduction rate, altered force-velocity relationship, increased anaerobic energy provision and increased thermoregulatory strain), although non-temperature-related mechanisms have also been proposed (e.g. effects of acidaemia, elevation of baseline oxygen consumption (V̇O2) and increased postactivation potentiation). It has also been hypothesised that warm up may have a number of psychological effects (e.g. increased preparedness). Warm-up techniques can be broadly classified into two major categories: passive warm up or active warm up. Passive warm up involves raising muscle or core temperature by some external means, while active warm up utilises exercise. Passive heating allows one to obtain the increase in muscle or core temperature achieved by active warm up without depleting energy substrates. Passive warm up, although not practical for most athletes, also allows one to test the hypothesis that many of the performance changes associated with active warm up can be largely attributed to temperature-related mechanisms.
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While warm up is considered to be essential for optimum performance, there is little scientific evidence supporting its effectiveness in many situations. As a result, warm-up procedures are usually based on the trial and error experience of the athlete or coach, rather than on scientific study. Summarising the findings of the many warm-up studies conducted over the years is difficult. Many of the earlier studies were poorly controlled, contained few study participants and often omitted statistical analyses. Furthermore, over the years, warm up protocols consisting of different types (e.g. active, passive, specific) and structures (e.g. varied intensity, duration and recovery) have been used. Finally, while many studies have investigated the physiological responses to warm up, relatively few studies have reported changes in performance following warm up. The first part of this review critically analyses reported changes in performance following various active warm-up protocols. While there is a scarcity of well-controlled studies with large subject numbers and appropriate statistical analyses, a number of conclusions can be drawn regarding the effects of active warm up on performance. Active warm up tends to result in slightly larger improvements in short-term performance (10 seconds, but 2). While active warm up has been reported to improve endurance performance, it may have a detrimental effect on endurance performance if it causes a significant increase in thermoregulatory strain. The addition of a brief, task-specific burst of activity has been reported to provide further ergogenic benefits for some tasks. By manipulating intensity, duration and recovery, many different warm-up protocols may be able to achieve similar physiological and performance changes. Finally, passive warm-up techniques may be important to supplement or maintain temperature increases produced by an active warm up, especially if there is an unavoidable delay between the warm up and the task and/or the weather is cold. Further research is required to investigate the role of warm up in different environmental conditions, especially for endurance events where a critical core temperature may limit performance.
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Reduced physical performance has been observed following the half-time period in team sports players, likely due to a decrease in muscle temperature during this period. We examined the effects of a passive heat maintenance strategy employed between successive exercise bouts on core temperature (Tcore) and subsequent exercise performance. Eighteen professional Rugby Union players completed this randomised and counter-balanced study. After a standardised warm-up (WU) and 15 min of rest, players completed a repeated sprint test (RSSA 1) and countermovement jumps (CMJ). Thereafter, in normal training attire (Control) or a survival jacket (Passive), players rested for a further 15 min (simulating a typical half-time) before performing a second RSSA (RSSA 2) and CMJ's. Measurements of Tcore were taken at baseline, post-WU, pre-RSSA 1, post-RSSA 1 and pre-RSSA 2. Peak power output (PPO) and repeated sprint ability was assessed before and after the simulated half-time. Similar Tcore responses were observed between conditions at baseline (Control: 37.06±0.05°C; Passive: 37.03±0.05°C) and for all other Tcore measurements taken before half-time. After the simulated half-time, the decline in Tcore was lower (-0.74±0.08% vs. -1.54±0.06%, p<0.001) and PPO was higher (5610±105 W vs. 5440±105 W, p<0.001) in the Passive versus Control condition. The decline in PPO over half-time was related to the decline in Tcore (r = 0.632, p = 0.005). In RSSA 2, best, mean and total sprint times were 1.39±0.17% (p<0.001), 0.55±0.06% (p<0.001) and 0.55±0.06% (p<0.001) faster for Passive versus Control. Passive heat maintenance reduced declines in Tcore that were observed during a simulated half-time period and improved subsequent PPO and repeated sprint ability in professional Rugby Union players.
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As the acceleration and deceleration demands of soccer are currently not well understood, this study aimed to profile markers of acceleration and deceleration capacity during professional soccer match-play. This within-player observational study required reserve team players from a Premier League club to wear 10 Hz Global Positioning System units throughout competitive matches played in the 2013/2014 competitive season. Data is presented for players who completed four or more games during the season (n = 11) and variables are presented according to six 15 min intervals (I1-6: 00:00-14:59 min, 15:00-29:59 min, 30:00-44:59 min, 45:00-59:59 min, 60:00-74:59 min, 75:00-89:59 min). During I6, the distance covered (total, per minute, and at high intensity), number of sprints, accelerations (total and high intensity), decelerations (total and high intensity), and impacts were reduced compared to I1 (all P ≤ 0.05). The number of high intensity impacts remained unchanged throughout match-play (P > 0.05). These findings indicate that high intensity actions and markers of acceleration and deceleration capacity are reduced in the last 15 min of the normal duration of match-play. Such information can be used to increase the specificity of training programmes designed for soccer players while also giving further insight in to the effects of 90 min of soccer-specific exercise. Interventions that seek to maintain the acceleration and deceleration capacity of players throughout the full duration of a soccer match warrant investigation.
Hypoglycaemia unawareness, is a major risk factor for severe hypoglycaemia and a contraindication to the therapeutic goal of near-normoglycaemia in IDDM. We tested two hypotheses, first, that hypoglycaemia unawareness is reversible as long as hypoglycaemia is meticulously prevented by careful intensive insulin therapy in patients with short and long IDDM duration, and that such a result can be maintained long-term. Second, that intensive insulin therapy which strictly prevents hypoglycaemia, can maintain long-term near-normoglycaemia. We studied 21 IDDM patients with hypoglycaemia unawareness and frequent mild/severe hypoglycaemia episodes while on “conventional” insulin therapy, and 20 nondiabetic control subjects. Neuroendocrine and symptom responses, and deterioration in cognitive function were assessed in a stepped hypoglycaemia clamp before, and again after 2 weeks, 3 months and 1 year of either intensive insulin therapy which meticulously prevented hypoglycaemia (based on physiologic insulin replacement and continuous education, experimental group, EXP, n=16), or maintenance of the original “conventional” therapy (control group, CON, n=5). At entry to the study, all 21 IDDM-patients had subnormal neuroendocrine and symptom responses, and less deterioration of cognitive function during hypoglycaemia. After intensive insulin therapy in EXP, the frequency of hypoglycaemia decreased from 0.5±0.05 to 0.045±0.02 episodes/patient-day; HbA1C increased from 5.83±0.18 to 6.94±0.13% (range in non-diabetic subjects 3.8–5.5%) over a 1-year period; all counterregulatory hormone and symptom responses to hypoglycaemia improved between 2 weeks and 3 months, with the exception of glucagon which improved at 1 year; and cognitive function deteriorated further as early as 2 weeks (p<0.05). The improvement in responses was maintained at 1 year. The improvement in plasma adrenaline and symptom responses inversely correlated with IDDM duration. In contrast, in CON, neither frequency of hypoglycaemia, nor neuroendocrine responses to hypoglycaemia improved. Thus, meticulous prevention of hypoglycaemia by intensive insulin therapy reverses hypoglycaemia unawareness even in patients with long-term IDDM, and is compatible with long-term near-normoglycaemia. Because carefully conducted intensive insulin therapy reduces, not increases the frequency of moderate/severe hypoglycaemia, intensive insulin therapy should be extended to the majority of IDDM patients in whom it is desirable to prevent/delay the onset/progression of microvascular complications.
To assess the relative roles of insulin and hypoglycaemia on induction of neuroendocrine responses, symptoms and deterioration of cognitive function (12 cognitive tests) during progressive decreases in plasma glucose, and to quantitate glycaemic thresholds, 22 normal, non-diabetic subjects (11 males, 11 females) were studied on four occasions: prolonged fast (n=8, saline euglycaemia study, SA-EU), stepped hypoglycaemia (plasma glucose plateaus of 4.3, 3.7, 3 and 2.3 mmol/l) or euglycaemia during insulin infusion at 1 and 2 mU·kg−1·min−1 (n=22, high-insulin hypoglycaemia and euglycaemia studies, HI-INS-HYPO and HI-INS-EU, respectively), and stepped hypoglycaemia during infusion of insulin at 0.35 mU· kg−1·min−1 (n=9, low-insulin hypoglycaemia study, LO-INS-HYPO). Insulin per se (SA-EU vs HI-INS-EU), suppressed plasma glucagon (∼20%) and pancreatic polypeptide (∼30%), whereas it increased plasma noradrenaline (∼R10%, p<0.05). Hypoglycaemia per se (HI-INS-HYPO vs HI-INS-EU) induced responses of counterregulatory hormones (CR-HORM), symptoms and deteriorated cognitive function. With the exception of suppression of endogenous insulin secretion, which had the lowest glycaemic threshold of 4.44±0.06 mmol/l, pancreatic polypeptide, glucagon, growth hormone, adrenaline and cortisol had similar glycaemic thresholds (∼3.8-3.6 mmol/l); noradrenaline (3.1±0.0 mmol/l), autonomic (3.05±0.06 mmol/l) and neuroglycopenic (3.05±0.05 mmol/l) symptoms had higher thresholds. All 12 tests of cognitive function deteriorated at a glycaemic threshold of 2.45±0.06 mmol/l, but 7 out of 12 tests were already abnormal at a glycaemic threshold of 2.89±0.06 mmol/l. Although all CR-HORM had a similar glycaemic threshold, the lag time of response (the time required for a given parameter to increase) of glucagon (15±1 min) and growth hormone (14±3 min) was shorter than adrenaline (19±3 min) and cortisol (39±4 min) (p<0.05). With the exception of glucagon (which was suppressed) and noradrenaline (which was stimulated), insulin per se (HI-INS-HYPO vs LO-INS-HYPO) did not affect the responses of CR-HORM, and did not influence the symptoms or the cognitve function during hypoglycaemia. Despite lower responses of glucagon, adrenaline and growth hormone (but not thresholds) in females than males, females were less insulin sensitive than males during stepped hypoglycaemia.
Formulation of oral rehydration solutions (ORS) is reviewed in the context of methods for measuring absorption of water and component substrates, transport mechanisms of substrates and water, requirements of the athlete, and effects of exercise on absorption. The triple lumen tube intubation perfusion method is the optimal technique for obtaining absorption data from the human small intestine during rest and exercise. Factors that must be considered when interpreting absorption data obtained by this technique include the role of the mixing segment in altering composition of the infused solution, defining optimal segment length, effects of ORS osmolality, and absorption of ''nonabsorbed'' indicators. Absorption data are applicable only to the test segment and may lack relevance to ORS transport proximal and distal to the test segment. Absorption rate of an ORS measured by perfusion may not correlate with absorption rate following ingestion. Transport of water, electrolytes, carbohydrates, and other solutes including glutamine and amino acids is considered in relation to ORS formulation. Factors affecting absorption of an ORS including the unstirred layer, motility, intestinal blood flow, and maximal absorptive capacity pf the alimentary tract are considered. Exercise per se at 30-70% VO2max far 60-90 min probably has minimal effects in limiting absorption of an ORS. Consideration relevant to supplying needs of the athlete during prolonged exercise in relation for ORS formulation are discussed.