]. With cessation of exercise, extra 02 is consumed in large quantities for removal d the lactic acid and now the RQ falls.

consumed]. With cessation of exercise, extra 02 is consumed in large quantities for removal d the lactic acid and now the RQ falls. Metabolism d carbohydrate and fat. Following stgnrficant points may be noted : (i) the blood lactate ( resting value 5-10 mg/ 100 ml) rises sharply and after severe sprinting may be around 200 mg/100 ml or even more (ii) the blood pyruvate and glycefol concentrations also rise during exercise (iii the btood glucose level shows no particular trend,. iiv) plasma free fatty acid level also rises. Fuel ot the muscles during exercise may be discussed at this stage. At rest or light exercise the fuel is fat. as (he exercise increases in severity. greater and greater proportion d glucose is used. (The term. luel". here means the type of food, protein.laLcartohydtale. utilized by, the muscles too Wain energy during the eaercise). In very hard exercise, glucose becomes the sole fuel It may take full one hour for the blood lactate to return to the preexercise value. In tournaments, therefore if an athlete has to compete in another event within one hout of competing the first.TIhe competetor definitely suffers from disadvantage (PT Usha. the Indian sprint queen had To participate in an event wrthin only 40 mm. after completing the first, in the 1986 Asiad). Skin and temperature changes in the initial phase of the exercise there is cutaneous vasoconstrictbn due to the sympathetic activity. This helps in redistribution of the Wood as mentioned earlier. As the exercise progresses, the body becomes hot. and the thetmoregulatory mechanism now starts acting (to keep the body cool). As a result. now. The cutaneous vasodilatation develops {so that The internal heat can be dissipated?. The sweat glands, also become active so that further heat dissipalbn is possible. The sweating causes further cutaneous vasodilatation. It should be understood that, for redistribution ot the blood, cutaneous vasoconstriction is required Cutaneous yasodilalation (with the aim to keep the body cooli zeopardises the redistribution to some extent and increases the load on the circulatory system.