The effect of
caffeine on shooting performance: Positive or Negative?
Caffeine (1, 3, 7-trimethylxanthine) is odorless and a bitter
alkaloid which is found in tea, coffee, cola drinks,
and chocolate (1, 4). See the Table 1 for
caffeine equivalents in common products (12).
Table 1. Estimated caffeine content in common
The amount of its metabolites level usually increases in the
blood within 15–45 minutes after caffeine intake, and reaches to the peak level
after an hour (1).
absorption of caffeine is slower when is consumed with a meal .But can be
absorbed faster by chewing caffeine-containing gum which allows for rapid
absorption through buccal tissue of the mouth. Caffeine is distributed to all
tissues very fast and passes easily through the blood-brain barrier for extending
its effects. The mean half-life of caffeine in the circulation is nearly 3–5 hour.
It means that can be interacted with many tissues for a long time (12).
January 2004, caffeine was one of several substances removed from the
Prohibited Substance List by the World Anti?Doping
Agency, the supplement is still being closely monitored in doping tests. This
strategy now permits the use of caffeine in sporting activities and competition
for the specific purpose of performance enhancement (1, 2).
(40 mg or 0.5 mg /kg) to moderate (300 mg or 4 mg/ kg) doses of caffeine
improve alertness, attention and reaction time, but steady effects are less on
memory and higher-order executive function, such as judgment and decision
making. Low and moderate doses of caffeine have not been shown to alter
significantly sensory functions including vision or hearing (12).Effects on
physical performance including time-to-exhaustion, time-trial, muscle strength
and endurance, and high-intensity sprints typical of team sports are observed
by dose of more than 200 mg (3 mg/ kg) (12). See the Table 2 for caffeine dose
associated with cognitive and physical effects.
2. Caffeine dose (mg/ kg body mass) associated with cognitive and
physical effects in both rested and sleep deprived individuals (12).
studies demonstrate that caffeine supplementation improves power, speed,
agility, attention, and reaction time in some sports. Now, caffeine is widely
used in various sports as an ergogenic aid. Unfortunately, there are limited
published studies on caffeine effects in precision activities such as shooting.
quantity of intentional ingestion of caffeinated products is safe and
appropriate for the shooting sport?
The results of one study on professional shooters showed
that taking 5 mg/kg of caffeine caused a significant increase in blood pressure,
a significant increase in heart rate but a significant decrease in shooting performance.
Moreover, taking 3 mg/kg of caffeine caused a significant increase in blood pressure.
But this amount of caffeine had no significant effect on the heart rate and
shooting performance. Decreased shooting performance maybe due to palpitation,
agitation and tremors in body of shooter. The shooter loses his / her
concentration and steady shooting position’s. So, he/she likely fires a
pendulum shot that increases the shooting error (1).In addition, caffeine can
effect on the nervous system and body temperature as effector factors .Studies
on military soldiers showed that caffeine can improve their shooting performances’
under conditions of sleep deprivation. But during conventional
conditions, a low dose of caffeine had no effect on
shooting performance and a medium dose of caffeine could be worsen shooting
performance (1, 7). The findings of other study showed that caffeine had
no ergogenic benefit with respect to reaction time, target tracking times and, particularly,
performance scores in the Olympic Double Trap. The treatment groups ingested 2
mg caffeine / kg of body weight and 4 mg caffeine / kg of body weight (2).
Consumption of 300 mg caffeine provided no performance benefit to shooting
accuracy and reaction time in traditional archery recurve bow discipline (8).
can see the results of one study on caffeine effects on Malaysian shooters
performances’ in below. Shooters ingested Nescafe classic coffee as caffeine
and Nescafe decaffeinated coffee as placebo (10).
Figure 2: Comparison Scores between Treatments
Figure 3: Comparison Scores between Rounds (1 round=10 shots) (10)
may help in increasing mental concentration and reducing perception of
tiredness but it didn’t show any effect in this study (10).
of caffeine supplementations
caffeine supplementation side-effects questionnaire in shooters revealed that
commonly associated side-effects, such as headache, anxiety, and tremor.
Caffeine administration can induce arm and hand tremor and interfere with
shooting performance. Arm trembling was reported after a single cup of coffee
or caffeine administration of 300–600 mg of caffeine. And also, 300 mg of caffeine
caused a marked increase in body sway 40 min after caffeine ingestion compared
with a placebo trial (3).
1: Physiological effects of caffeine (9).
caffeine ingested in excessive amounts for a long period, caffeine reaches to toxicity
level (caffeinism), which including below symptoms:
system symptoms : Headache, lightheadedness, anxiety, agitation, tremulousness,
perioral and extremity tingling, confusion, psychosis, seizures
: Palpitations or racing heart rate, chest pain
symptoms: Nausea and vomiting, abdominal pain, diarrhea, bowel incontinence,
agree that there is no health risk with consumption of up to 400 mg (?5.5 mg/ kg for a 75 kg individual) of caffeine doses per day by
healthy adults (12).
is recommended that shooters look for other useful ways for improving their performances’
before considering the use of caffeine products as a supplementation. However,
if you are interested in using caffeine products during shooting training sessions,
please request medical supervision to ensure the level of consumption is safe
and appropriate. Some athletes experience a perceived or psychological benefit from
the ingestion of caffeine products. This means some individuals are ‘caffeine
responders’, while others are ‘no responders’ with caffeine consumption. For
both of them, we advise to follow a medical consult before consumption (2).