Beta-blockers and archery: Ergen 2021 study

Fifteen archers from national teams shot four times, blinded, after a single dose of a selective beta-blocker (bisoprolol 5 mg), a non-selective one (propranolol 40 mg), a placebo, and in a control condition with nothing at all. The drugs did to the heart what is expected of them: heart rate during shooting fell by 12.8% with bisoprolol and by 8.6% with propranolol, and standing resting heart rate went from 94.0 beats per minute in the control condition to 76.5 with bisoprolol and 80.5 with propranolol, while with placebo it stayed at 89.7.

On the target, nothing changed. The analysis finds a difference in scores in the direction of a decline with propranolol, but after correction for multiple comparisons no comparison remains significant. Aim point fluctuation, measured in centimetres on the target over the three tenths of a second before release, was 8.29 cm in the control condition and 8.41 cm with placebo, 7.86 cm with bisoprolol and 9.05 cm with propranolol: the two drugs differed from each other, neither differed from control. The path travelled by the centre of pressure over the same interval was 11.03 cm in control, 11.86 cm with placebo, 10.29 cm with bisoprolol and 10.26 cm with propranolol, with no differences.

The correlations between score and movement are negative in every condition, that is, the more the sight moves the lower the score, and they reach significance with placebo (-0.776) and propranolol (-0.516). The score with bisoprolol was related to the distance travelled by the centre of pressure (-0.675).

A crossover design, with the order drawn at random, a placebo among the four conditions and neither archer nor assessor told which had been given: every archer went through all four, with seven days between testing days to wash out the substance. Control shots were taken 24 hours before any administration. The participants were fifteen men from national teams with at least four years of training, mean age 20.5 years, height 177.9 cm, weight 78.3 kg, on no medication and consuming no alcohol or caffeine during the testing period.

Each day began at nine o'clock in an indoor hall, to keep ambient conditions constant, with the archers asked to prepare as for a normal competition. Resting heart rate was first measured lying down, as the average of the last minute of twenty, then standing for four minutes. Two hours after administration the archers shot 30 arrows, three arrows per end over ten ends with the two minutes allowed by the rules, then waited a further two hours, repeated the resting measurement and shot another 30 arrows: 60 arrows per condition in all, with the two windows chosen to match each drug's time to peak concentration. Shooting was at 18 metres with judges and indoor rules, in pairs as in a match, for about 45 minutes.

Aim point fluctuation was recorded with an infrared laser pointer fixed to the bow and two modified cameras, with the infrared filter removed and telephoto lenses, calibrated every day and converted into centimetres using the known target height; the beam is invisible to the eye, so it does not disturb the archer. The centre of pressure was measured with two force platforms of 120 by 120 centimetres, each with four load cells, computing the distance travelled. Heart rate was recorded every second with a heart rate monitor. All mechanical variables were taken over the three tenths of a second before release.

Fifteen men, all of one standard, in a simulated competition. The authors flag the main limitation themselves: archers will not carry sensors on their bodies and bows in a real match, so the setting stays the laboratory, and heart rate during these shots was lower than values recorded elsewhere in competition. If the effect of a beta-blocker depends on arousal, measuring it when arousal is already low narrows the room in which an effect could appear. The second stated limitation is the single dose.

Absolute scores do not appear in the text, only in the figures, so how many points are at stake cannot be read. The sample is male only, a choice justified by the difference in heart rate between the sexes, and the result does not extend to women. With fifteen people, the absence of a difference does not rule out a small effect: the study can say that no advantage was seen, not that there is nothing below a certain size.

One internal inconsistency should be noted: the discussion states that all the correlations between aim point fluctuation, centre of pressure and score were non-significant, while in the results three of them are. The correlations, besides, are computed on fifteen observations per condition and should be read with care.

The practical result contradicts a widespread idea: lowering heart rate does not raise the score. Here the heart rate was lowered pharmacologically, clearly and measurably, and the score stayed where it was; sight movement and body movement on the platforms did not improve either. If a slower heart were the key to steadiness, this was the most direct way to show it.

The other half of the picture stands, and this study supports it: where the sight moves less, the score is higher. It is aim point fluctuation that correlates with points, not heart rate.

Two points need stating. Beta-blockers are prescription drugs, and the study recalls that they have been banned in archery since 1985 on the strength of older work in pistol shooting: this registry describes what was measured and does not get into their use. And the registry gives no medical guidance: anyone taking these drugs for a health condition discusses them with their own doctor, not with a study page.