Quick Answer. In an officially-sanctioned MLB baseball game, there are 9 innings. If the home team is ahead in the top of the ninth and earns 3 outs, the game ends at 8 1/2 innings. If the game is tied after the away team earns 3 outs in the bottom of the ninth, the game goes into extra innings. Keep Learning.
Gas Exchange During Exercise. During exercise, your body needs more energy, which means your tissues consume more oxygen than they do at rest. Consuming more oxygen means you will also produce more carbon dioxide because your metabolic rate is elevated. The ratio of carbon dioxide produced per oxygen consumed also increases during exercise because a shift from fat to carbohydrate utilization takes place. At the most challenging work rates, you burn carbohydrates exclusively and produce 1.0 liter of carbon dioxide for every liter of oxygen you consume.
Your heart rate increases when you exercise. Photo Credit Jupiterimages/Stockbyte/Getty Images. Your heart rate increases when you exercise, because you are working harder. How much your heart rate increases depends on the intensity of your exercise and how fit you are. Exercise experts differ on how high your heart rate should be during exercise, but they agree that it needs to be substantially higher than your resting heart rate to improve your cardiovascular fitness.