The purpose of this research study is to understand how different kinds of exercise affect the human body and the health of the heart and lungs.Participants will exercise in different protocols on a bicycle ergometer or treadmill. This research could lead to improved and more accurate fitness assessment and pave the way to an improved personalized exercise program in health and illness.

The purpose of this research study is to understand how different kinds of exercise affect the human body and the health of the heart and lungs. For example, some people like to exercise continuously for relatively long periods of time while others like to exercise for short periods of time with rest periods in between. Children tend to exercise in frequent bouts of brief exercise interspersed with periods of rest. Also, some people like running or treadmill exercise while others like to work out on stationary bicycles. To date, standard exercise testing is based on a century-old paradigm used predominantly for adults that involves maximal exercise protocols (cardiopulmonary exercise testing-CPET). Moreover, different but widely used exercise modalities such as cycle ergometer and treadmills are currently impossible to compare in children, and this has limited the clinical and research application of such testing in the pediatric age-range. A major premise of this laboratory is that laboratory testing of cardiopulmonary fitness in children should be based on protocols that mimic naturally occurring patterns of exercise in children, rather than those that have been artificially employed to assess maximal efforts in adults. This research project designed to begin the process of systematically identifying protocols can be best used for children and young adults. Participants will exercise in different protocols on a bicycle ergometer or treadmill. This research could lead to improved and more accurate fitness assessment and pave the way to an improved personalized exercise program in health and illness.

Inclusion Criteria:

• Between the ages of 7-35 years old without any known respiratory, cardiac or metabolic disease
• Determined to be in good health by preparticipation history
• No evidence of disease or disability that would impair participation in an exercise testing
• No chronic prescribed medication

Exclusion Criteria:

• Other limitation which in the eyes of the physician that would preclude ability to perform exercise testing
• Use of illegal drugs or abuse of alcohol
• Pregnancy or breastfeeding

During the 30 min exercise for each of the two sessions.

Not different from clinicaltrial.gov definition

The same order of exercise test modalities may influence the second test session. Supramaximal test was not performed.