___ drugs focus on efforts to change the concentration of neurotransmitters in the brain. For example, selective serotonin reuptake inhibitors concentrate serotonin in synapses between neurons.

Why is it so important to have a lifetime commitment to training? a-it takes your entire life to become fit b-it keeps you from becoming bored c-you will lose strength and endurance once you stop exercising d-it increases your motivation in life