Science for practice

Diagnosing the Functional State of the Cardiovascular System in Weightlifters

A. F. Sinyakov, S. V. Stepanova, Cand. Sc. (Medicine), GTsOLIFK

English summary of Tyazhelaya Atletika. Ezhegodnik 1985 (Moscow: Fizkultura i Sport, 1985), pp. 37–40: the text is paraphrased, not translated; data tables are given in full with English labels.

In weightlifters the cardiovascular system works under difficult conditions, because the special exercises involve breath-holding and straining. Weightlifting generally benefits health, but irrational training, excessive loads or training while ill can produce pathological changes such as electrocardiographic abnormalities or abnormal blood pressure.

Sports medicine attends closely to this system because it limits working capacity and its response shows whether sport helps or harms. The authors used a range of tests: the Kevdin test (40 squats in 30 s), the PWC 170 test of working capacity, electrocardiograms and polycardiograms at rest and under load, telemetry, echocardiography and straining tests.

Electrocardiography and resting heart rate

Electrocardiography is an accessible, highly informative method. Taken at rest (before and after exercise) and during training, it shows how the heart responds to the loads, allows timely correction of training and exposes abnormalities early. It usually reveals nothing peculiar in weightlifters (L. A. Butchenko, 1963; A. N. Vorobyov, 1977).

Resting heart rate, measured during the day, ranged from 44 to 83 beats/min and averaged 62. Sinus bradycardia (below 60 beats/min) was found in 46% of the lifters, mostly moderate (50–59). In 2.9% the rate exceeded 80, untypical of well-trained athletes and a sign of fatigue: all of them had health problems (chronic infection, electrocardiogram changes, raised blood pressure) and coped worse with training. This agrees with other authors (M. B. Kazakov, 1961; Vorobyov, 1977). Overall the lifters' electrocardiogram resembled that of healthy untrained young men; 68% had non-pathological sinus arrhythmia. In 20.9% the end part of the ventricular complex (S–T segment and T wave) changed under heavy myocardial load. These athletes were treated and, in periods of hard training, given preventive medication (potassium orotate with inosine, multivitamins).

Echocardiography

Echocardiography, proposed by Swedish scientists in 1954, is a relatively new method. Ultrasonic waves, generated by alternating current in a piezoelectric crystal, are directed at the heart; structures of different density reflect them back, and the echo is picked up by a sensor, amplified and shown on an oscilloscope screen, from which a camera records it. The method gives the structural and functional features of the heart: thickness of the posterior wall of the left ventricle, end-systolic and end-diastolic volumes of its cavity, aortic orifice diameter, size of the left atrium and right ventricle, and contractility. Sports cardiology adopted it only recently (N. D. Graevskaya, G. A. Goncharova and G. E. Kalugina, 1976; A. G. Dembo and others, 1978; Yu. K. Shkhvatsabaya, 1979; A. G. Dembo, E. V. Zemtsovsky and B. A. Frolov, 1980).

The lifters were examined lying down with the Soviet UZKAR-3 echocardiograph, the sensor in the 3rd–4th intercostal space 2–3 cm outward from the left edge of the sternum. Several cardiac dimensions clearly depended on physical development, so values were judged in absolute and relative terms. In heavy classes absolute dimensions were substantially larger, but relative values were close to those of healthy untrained men. Weightlifting therefore does not substantially affect cardiac morphology, and no impairment of myocardial contractility was found.

Exercise tests

Load tests, non-specific and specific, were emphasised: bicycle ergometry and lifting the barbell to the chest, the Kevdin test, and 15 s of running on the spot at maximum tempo. Lifters, especially heavy ones, usually ran with technical faults, so the authors preferred the squats.

Heart rate usually rose moderately, averaging 48% above the initial level in the first 10 s of recovery; systolic pressure rose 29%, diastolic fell 10.5% and pulse pressure rose 102%. In 30% of the athletes heart rate and blood pressure recovered by the third minute of rest, in the rest more slowly. The response was normotonic in 95%; atypical responses to the Kevdin test (5%) mostly stemmed from training breaches. Athletes with raised blood pressure usually recovered slowly and responded hypertonically.

After the 15-second run heart rate rose 81.1%, systolic pressure 19.5%, pulse pressure 87.8%, and diastolic pressure fell 19.4%. In 88% the response was normotonic, with recovery by the 3rd–4th minute; in 12% it was atypical, with no recovery within the 4 min of observation. The run raised the pulse more than the squats, but changes after both tests were fairly small. Atypical responses were linked to training breaches and chronic infection (carious teeth, chronic tonsillitis). At repeat examination at the end of the preparatory period, heart rate and systolic pressure rose less and recovered sooner, a sign of improved functional state.

The straining test

For a more objective assessment in in-depth examinations the authors used a straining test as the specific one. Straining during lifting strongly affects the autonomic systems. With breath held, intrathoracic, intrapulmonary and intra-abdominal pressure rise, less blood reaches the right heart and the right ventricle ejects less. Narrowing of the fine pulmonary vessels reduces the flow into the left ventricle, and stroke and minute volumes fall sharply, though compensatory acceleration of the rhythm limits the fall in minute volume. Blood pressure shifts too but soon recovers.

By most accounts of straining tests (Valsalva, Flack, Burger), systolic pressure normally rises slightly during straining and returns to the initial level by the 40th second afterwards; a fall of more than 10 mmHg that does not recover by then indicates poor regulation. Heart rate rises; in athletes well adapted to straining the rise is slight (1–3 beats per 5 s at the start) and soon stabilises, and 5–8 s after straining it slows to below the initial level for a time.

The seated athlete's electrocardiogram gave the heart rate (in 5-second intervals over 20 s), then blood pressure was measured. After a deep breath the athlete exhaled into a rubber tube with a mouthpiece connected to a Riva-Rocci apparatus, holding the pressure at 40–60 mmHg for 20 s. Heart rate was recorded during and for 20 s after straining; pressure immediately afterwards and 40 s later.

Tables 1 and 2 give mean results. Systolic pressure rose on average by 19 mmHg and diastolic by 5; by the 40th second it had practically recovered (systolic only 2 mmHg above initial). The response was satisfactory in 27% of the lifters and good in the rest (systolic up 5–15 mmHg, diastolic unchanged or up 5–10, recovery by the 40th second, heart rate up 1–2 beats per 5 s). Table 3 compares the start of the preparatory period with its end, 1–2 weeks before competition: systolic pressure rose less the second time, by 12 against 18 mmHg, showing better adaptation to this kind of load.

Table 1. Blood pressure change in weightlifters during the straining test (means)

Table 2. Heart rate of weightlifters in 5-second intervals during the straining test (means)

Table 3. Blood pressure change in weightlifters during the straining test at the start and end of the preparatory period (means)

Reliable diagnosis is possible only with a complex of methods. The data given, gathered over several years from 460 Master-of-Sport weightlifters (trade-union sports society teams and the USSR national team), can serve as reference values for highly qualified athletes.