Final answer:
The two types of muscle groups used in the summation of force are agonist and antagonist muscle groups. Agonist muscles are responsible for creating movement, while antagonist muscles work in opposition to create stability.
Step-by-step explanation:
The two types of muscle groups used in the summation of force are agonist and antagonist muscle groups. The agonist muscle group is used first in a physical activity.
Agonist muscles are responsible for creating movement at a joint, while antagonist muscles work in opposition to the agonist muscles, helping to control the movement and provide stability.
Two examples of agonist muscles are the biceps brachii and the quadriceps femoris. Two examples of antagonist muscles are the triceps brachii and the hamstrings.