Heart and brain while aiming in archers: Salazar 1990

During aiming, the hearts of 28 archers from the United States national teams did not slow down: they sped up. Over the last 3 to 4 seconds before release, heart rate rose on average from 100.7 to 104.2 beats a minute, and comparing it with breathing pattern (breathing in, breathing out, holding) showed no link. Mean heart rate while shooting (104.4) was almost the same as when holding the bow at full draw without shooting (103.0), and much higher than at rest looking at the target (87.0) or holding a 2 kg bow at full draw (83.5). The last figure was lower than at rest too, and the authors read it as a sign that attention-related slowing does exist but disappears when the physical effort is large.

The electroencephalogram recorded over the temples peaked at 12 Hz, in the alpha band, in both hemispheres, with more power on the left. Over the three seconds before release the right hemisphere did not change, while on the left power rose at 10, 12 and 24 Hz. Comparing each archer's four best arrows with their four worst, in the final second there were no differences on the right; on the left the worst arrows had more power at 6, 12 and 28 Hz. Going from rest to shooting, the dominant activity on the left narrowed to between 12 and 14 Hz, while on the right it spread across more frequencies.

The archers were 13 men and 15 women, all right-handed, from the United States junior and senior national teams, aged 13 to 36 (mean 21). Each was tested alone in a large gymnasium under four conditions in random order: normal shooting with their own bow, a draw weight of 14 to 22 kg; holding the bow at full draw while looking at the target without shooting; drawing a 2 kg bow while looking at the target; and resting while looking at the target. In the shooting condition they shot 16 arrows at 45 metres, with five minutes' rest after the first eight; in the others, eight trials of 8 seconds were recorded. A session took 90 to 120 minutes.

A polygraph sampled at 250 Hz the electrocardiogram, the EEG at T3 and T4 (left and right temple), movements of the non-sighting eye and breathing, through a thermistor in a mask over nose and mouth. A sensor fixed to the stabiliser marked the clicker falling and the release. Heart rate was worked out from the five beat-to-beat intervals before release; the EEG over three one-second epochs, in 13 bands of 2 Hz between 5 and 31 Hz, with trials containing blinks discarded. Each arrow was scored as its distance in centimetres from the centre of the target.

Two electrodes, one per temple, say little about where the changes happen, as the authors point out. The comparison of best and worst arrows uses four shots each out of sixteen, and there are many statistical tests (13 bands, two hemispheres, several time points): the authors themselves call for replication, especially of the 24 Hz finding. The idea that lower power on the best arrows reflects a more "efficient" brain is their interpretation, not a measurement.

Some statistical details do not add up for 28 archers: for the rise in heart rate the reported degrees of freedom are 1 and 32, and for the comparison between conditions 2 and 50. The non-shooting conditions last 8 seconds and contain no release, so they are not fully comparable with shooting. Testing was in a gymnasium, at 45 metres, with electrodes and a mask on the face, far from competition conditions. The type of bow is not stated, although the clicker suggests recurve. Finally, the heart rate result is a group mean: the paper says each archer's pattern was classified, but it does not report how many slowed down and how many sped up.

For archers the clearest finding concerns the heart. The idea that the heart slows in the last seconds of aiming, which came from studies of rifle shooting and golf, did not show up in these national-level archers: holding a 14 to 22 kg bow at full draw raises heart rate, and the effort masks any effect of attention. A heart rate that climbs at full draw is therefore not, in itself, a sign of anxiety or poor focus. The authors cite later work of theirs in which beginners with lighter bows did slow down before release: the outcome may depend on draw weight and level.

The brain findings are best taken as a lead for research: on the worst arrows there was more activity at some frequencies over the left temple, but with two electrodes and four arrows each way there is nothing here to train. In the registry the study counts against the claim about heart rate deceleration before release, and it is one of the first papers on elite archers to measure it.