A study was carried out to investigate the application and method of adjusting a cant, and its effect in ski boots. Forty-two professional ski instructors were asked by questionnaire about the application and method of adjusting a cant, and its effect, etc. Simultaneously they were also checked regarding the alignment of the lower extremities. In order to reveal the effect of cant quantitatively, an experiment was performed on a ski-slope. The inclination of the axis of the lower leg was measured at an angulation position on the slope after placing a 1-mm, 3-mm, or 5-mm thick plastic medial wedge between the boot and the ski, so as to give valgus inclination to the heel.
The results and conclusions are summarized as follows ;
1) Twenty-seven of the forty-two subjects used a cant, and about one third of them stated that its effect was unknown.
2) Valgus cant ( (+) cant) had the effect of improving edge-control and decreasing the inclination of the lower leg, whereas varus cant ( (-) cant) had the effect of smoothing the sliding of the ski tail in the latter half of a turn.
3) There was little change in the axial inclination of the lower leg, even when a 5-mm-thick plastic medial wedge was placed between the boot and the ski.
4) A cant compensates not for static malalignment of the lower extremities but for deficiency of joint movement, and should be adjusted according to a skier's individual technical problem, for example poor edge-control, utilizing its merits described in 2) .

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Single-stage treadmill exercise testing (7° inclination, at 50 m/min for 5 min) was performed in 143 hospitalized patients (aged 32-90 years, mean 64 years ; 78 males and 65 females) who required non-cardiopulmonary operations. Systolic blood pressure was recorded at rest and every 1 min during and immediately after exercise, together with pulse rate and ECG recordings. There was no difference in the systolic blood pressure response to exercise between the male and female patients aged 50 to 69 years, although the increase in pulse rate during exercise was greater in the female patients. Comparing the male patients aged 70 years or more with those aged less than 70 years, the increase in systolic blood pressure during and immediately after exercise was greater in the former than in the latter. Hypertensive patients showed a more exaggerated systolic blood pressure response to exercise than the normotensive patients, although the difference in systolic blood pressure at rest between the two groups was slight on the day of the exercise testing. The incidence of hypertensive episodes after surgery was significantly higher in patients whose systolic blood pressure during exercise had been more than 200mrHg (4/26) than in patients whose systolic blood pressure during exercise had been below 170 mmHg (0/41) . These results indicate that measurement of blood pressure during exercise testing is a useful means of predicting the blood pressure response under stress states in surgical patients.

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The relationship between relaxation time and muscle fiber composition was investigated in 16 males.
A highly positive correlation was found between muscle fiber composition and relaxation time. In addition, higher proportions of fast-twitch fibers were associated with longer relaxation times, indicating that the fast-twitch fiber has a longer relaxation time than the slow-twitch fiber.
Multiple regression analysis, which was conducted to investigate the suitability of relaxation time as a model for estimating muscle fiber composition, revealed that the T 1 and T 2 were significantly related to muscle fiber composition.
Therefore, the results of the present study indicate that relaxation time obtained by MRI can be used to estimate muscle fiber composition.

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We studied the nature of biphasic changes in serum creatine kinase (CK) activity with transient weight training.
Six untrained healthy men (21-24 yr) participated in the programme. Six different types of weight training (70-80% maximum muscular strength) were imposed. Blood specimens were collected on nine separate occasions and CK activity, calcium (Ca), inorganic phosphate (Pi), zinc (Zn) and polyamine concentration were measured.
Muscle soreness was also examined by asking the men to fill out a questionnaire.
Muscle soreness appeared one hour after training and was considerable one and two days after the training.
CK activity showed a typical biphasic change. The extreme mean values (highest or lowest) of Ca, Pi, Zn and polyamines appeared between two and three days after the training. This period of time corresponded to that between the first and second peaks of CK activity. The first peak of CK activity after weight training was assumed to be related to muscle soreness. We propose that changes in blood Ca, Pi, Zn, polyamines and muscle soreness reflect a series of different histopathological reactions including muscle damage, repair and regeneration in subjects given transient weight training. Each peak of the biphasic change in serum CK activity may be different in nature, histologically and/or biochemically.

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