Cadence and Intensity Across the Adult Lifespan

Overview

The purpose of this study is to determine and link cadence (the number of steps taken in a minute) to the intensity of physical activity (e.g. low-, moderate- and vigorous-intensity) in adults (21-85 years old). The investigators anticipate that cadence will be a good indicator of exercise intensity. Identifying how cadence relates to activity intensity will allow for physical activity guidelines to be communicated to the public in a manner that is more accessible to the lay person.

There will be up to two lab visits for CADENCE-ADULTS participants, all of which will be completed in the Physical Activity and Health Lab at University of Massachusetts Amherst. Participation will include: orientation to the experiment, consent, physical examination and testing. The entire research protocol will last between 3.5-4.5 hrs. For all participants the first visit will consist of an orientation to the project, screening, informed consent, physical exam and ECG (if necessary, see below), as well as the graded treadmill walking protocol. Pre-visit: Prior to coming to the laboratory participants will undergo a phone screening in order to identify interest, outline basic inclusion/exclusion criteria and give a brief description of the study protocol. If interested participants will be scheduled for their first visit and be given the instruction to arrive at the laboratory having observed at least a 4-hour fast. The reason for required fast is that metabolic responses to exercise are affected by food intake. By fasting for 4 hrs prior to the exercise testing window the investigators insure standardization of metabolic responses to exercise. Orientation: Participants will be taken through a slide orientation session where all aspects of the study will be covered. This slide set has both written and pictorial descriptions of the different phases of the experiment, eligibility criteria, participant rights, compensation and confidentially. At this time participants have the opportunity to ask any questions of the experimenters that they would like. Consent: If after being presented with the orientation information a person would like to enroll in the study they will be given the informed consent document. They will be given ample opportunity to read through the document and decide if they would like to sign the paper and enroll in the study. Pre-testing screening: Once the consent paperwork is signed participants will have their height, seating height, body weight, body fat percentage, BMI, and waist circumference taken. Questions will also be asked to ascertain date of birth, gender and race/ethnicity. Participants will then be taken through a series of screening questionnaires to assess cardio-metabolic risk via the the most recent edition of the American College of Sports Medicine (ACSM) Resource for The Health Fitness Specialist and also the American heart Association's (AHA) risk stratification recommendations presented in the same ACSM resource. Risk will be assessed in the following ways: For participants considered low risk (men 21-44 years of age and women 21-54 years of age, asymptomatic and with ≤ 1 risk factors) no physical examination and resting ECG is necessary prior to enrolling in the study. Those considered at moderate risk (men 45-69 and women 55-69 years of age, asymptomatic with ≥ 2 risk factors) will require the physical examination and resting ECG prior to enrolling in the study. Those considered to be high risk (symptomatic, or with known cardiac, pulmonary or metabolic disease), or found to be at high risk following risk stratification, will require medical supervision during the submaximal treadmill exercise protocol. All participants who are 61-85 years of age will require a physical examination and resting ECG prior to enrolling. Physical Exam and ECG: A physical exam will be conducted by our study staff under the guidance of our medical examiner (Dr. Chipkin) to assess for medical conditions that may interfere with exercise protocol. In addition, this is being performed to ensure participant safety during exercise protocol . Electrocardiogram (ECG). A 12-lead electrocardiogram will be performed by study staff and reviewed by a clinical exercise specialist (e.g., clinical exercise physiologist) or MD prior to exercise protocol. All testing will be overseen by trained study staff with an MS or PhD in Exercise Science/Physiology or BS in Kinesiology. These accommodations meet the latest ACSM (10 Edition, Guidelines for Exercise Testing and Prescription) and AHA criteria for exercise protocols. Experimental Testing: Immediately prior to exercise testing participants will be outfitted with a number of non-invasive devices to measure/monitor physical activity. Additionally they will be outfitted with a wireless metabolic mask to measure gas exchange for a criterion measure of energy expenditure. Participants will complete both the treadmill testing and mock free-living activities while physical activity and oxygen uptake are continually and concurrently measured. Each speed on the treadmill and each free-living activity will be performed for 5 minutes with a 2 minute rest between each activity. Participants will complete each activity at their preferred level of effort. Treadmill walking: Participants will then complete a series of walking bouts on a treadmill while their physical activity and oxygen uptake are concurrently assessed. The walking bouts start at 0.5 miles per hour and end at 6 miles per hour (0.5 miles per hour increments). Treadmill testing will be terminated when any of the following criteria are attained: upon any natural tendency to reach out to use the hand rails to steady and/or support themselves, following completion of the fist bout when their heart rate attains 75% of age-predicted maximum heart rate(indicative of having achieved vigorous intensity), participants identify as having a 14/20 or greater level of exertion on a Borg Rate of Perceived Exertion Scale, following completion of first bout when the participant naturally selects to run instead of walk, following completion of a bout at 6.0 mph, or before any of the above criteria, as the participant prefers, reflecting their personal tolerance. Free-Living Activities: Participants will rest in chair, watch a portion of a movie while seated in a chair, complete seated computer work, walk up and down a set of stairs, fold laundry while standing, and vacuum the floor. Participant will then complete a continuous walk for 5 minutes at their desired pace. This walk will be completed in a corridor with an electronic gait mat (GaitRite, Inc., USA) covering a portion of the walking course. Following completion of the testing, participants will be given a small snack and drink and will be monitored to ensure it is safe for them to return to their day. NIH NIA supplement award R01AG049024-05S1, start date May 2018 - In addition to the above procedures related to the CADENCE-Adults parent award, participants aged 61-85 may also participate in an optional component of the study related to the supplement award. This will include: 1 week of physical activity monitoring: An additional 7 consecutive days of physical activity monitoring (ActiGraph GT9X and New Lifestyle DigiWalker SW-200). Participants will wear the devices on their waist for 24 hours a day and maintain their usual physical activity levels. They will also be asked to complete a daily physical activity log. Participants will be to complete this within twelve weeks of their final visit to the physical activity and health lab. In addition, they will also be asked a series questions regarding their physical activity history over the past month (CHAMPS questionnaire). AND Peak aerobic fitness treadmill protocol (modified Balke protocol). Participants will will first walk for a warm-up period of 6 - 10 minutes at a comfortable walking speed. Treadmill speed will then be set to elicit 70-80% of their age-predicted max heart-rate (HRmax), and remain constant for the entirety of the protocol. This speed will be determined based on the speed and heart rate relationship observed during the previous treadmill test (sub-maximal treadmill protocol). Specifically, if 70% of HRmax was reached during the previous test, the peak aerobic fitness test will start at the first speed at which this heart rate threshold was first observed. If the previous test was terminated before 70% of HRmax (e.g., the participant naturally chose to run or achieved a rating perceived exertion consistent with a vigorous intensity), the speed for the peak protocol will be set at 0.5 mph faster than the previous test's termination speed. If the previous test was terminated before 70% of HRmax was reached because the participant: indicated they wished to stop the test, the researchers stopped the test due to safety concerns, they reached for the handrail or became unsteady, or they achieved a systolic blood pressure \>200 mmHg or diastolic blood pressure \>110 mmHg; then the speed for the peak protocol will be set 0.5 mph slower than the previous termination speed. Participant will first walk at the pre-determined testing speed for 2 minutes at a grade (incline) of 0%. The grade will then be increased from 0% to 4% after 2-minutes, then to 6% after 4 minutes, and then by 2% every minute thereafter until they indicate that they want to stop (voluntary exhaustion), or earlier for any safety-related reasons. During this testing, the participant will be outfitted with the Oxycon Mobile to assess peak aerobic fitness. For safety reasons, participants will be required to wear the ECG and BP equipment to monitor their cardiovascular responses during this test. A trained staff member will be on hand to operate this equipment, monitor responses and ensure safety procedures are followed. Our medical investigator, Dr Stuart Chipkin will be on hand to supervise all peak treadmill protocols. Participants will be required to complete this a minimum of 7 days, and maximum of 12 weeks from the the submaximal treadmil protocol in the parent award.

Conditions

Interventions

Eligibility

Locations (1)

Outcomes