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.
When you exercise, the muscles you use require more energy. When exercise can be sustained, this demand is met primarily by aerobic means. Aerobic energy production in muscles results in increased gas exchange at the lungs, because more oxygen is taken in and more carbon dioxide is released.
A level between 50 and 70 percent of VO2 max represents a transition phase for most people. Above 70 percent of VO2 max, the aerobic system does not produce energy fast enough, thereby causing individuals to rely more and more on their anaerobic systems. Another important factor that must be considered when examining the relationship between the production of energy and exercise intensity is lactic acid.