Archers' hearts and sport: Dai 2002 study

In 51 male university students from six sports, 7 of them archers, the authors used Doppler ultrasound to measure left ventricular mass and the diameter of seven arteries: both common carotids, both radial arteries at the wrist, both dorsalis pedis arteries on the top of the foot, and the aorta. All values were also divided by body surface area to remove the effect of body size.

The archers had the lowest ventricular mass in the sample, 148.3 grams (82.6 g/m²), close to the sprinters and far from the long-distance runners (218.1 g, 131.4 g/m²). The sum of arterial diameters was also among the lowest (43.3 mm, 24.7 mm/m²), and the aorta, scaled to body surface area, was the smallest (11.0 mm/m²). The radial artery is the exception: at 1.5 mm/m² the archers were second only to the weightlifters (1.7), level with the long-distance runners and above the swimmers and sprinters. The authors read this as a local adaptation of the arteries to the specific work of the sport. The sum of arterial diameters correlated with ventricular mass (r = 0.657, and r = 0.893 after scaling to body surface area).

The athletes were students at Nippon Sport Science University, with mean ages between 18.8 and 20.1 depending on the group: 7 archers, 10 weightlifters, 10 swimmers, 8 sprinters, 9 middle-distance and 7 long-distance runners. Measurements were taken with a Hewlett Packard M2410A ultrasound system. Ventricular mass was calculated in M-mode, lying on the left side, from septal thickness, posterior wall thickness and the ventricle's diastolic diameter; arterial diameters were measured in B-mode, lying supine, with the probe placed along the course of the artery, except the aorta, measured at the valve annulus in the same left-side position used for the heart. Body surface area was derived from height and weight using the Takahira formula.

Means are reported with the standard error and groups compared with Fisher's PLSD test. The paper also gives resting blood pressure and heart rate: the archers had 119.4 over 68.1 mmHg and 69.1 beats per minute, with a mean height of 170.7 cm and weight of 62.7 kg.

There are 7 archers, and all the groups are small. The study is cross-sectional: it compares students in different sports without knowing what they were like before, so it cannot separate the effect of training from the selection of who takes up which sport. Bow type, draw weight, years of shooting and training hours are not given, and for the radial artery the paper reports a single value, without distinguishing the bow arm from the drawing arm, which is exactly the figure needed to talk about a local adaptation. There is no sedentary group, so it is not known whether the archers' values differ from those of non-athletes of the same age.

The text and the chart do not make clear whether the heart-artery correlations were calculated on the 51 students or on the means of the six sports; in the latter case they rest on six points. The text is in Japanese, with the abstract and tables in English, and one of the ages given in the text (middle-distance runners, 20.1) does not match the table (18.9).

For an archer the study confirms something intuitive: archery does not move the heart towards the profile of an endurance athlete. The archers' ventricular mass and aortic diameter were among the lowest in the sample, close to the sprinters. The one distinctive feature is a relatively wide radial artery, consistent with repeated work of the hand and forearm, but with 7 archers and no distinction between the two arms it remains an indication.

It is not a basis for designing training, nor a health assessment, which is in any case a matter for a doctor. In the registry this record serves as a physiological description of young archers compared with other sports, useful mainly to anyone wondering what kind of cardiovascular load shooting involves.