EXSC 230: Physical Activity Guidelines (PAG) for Americans

PAG Note (muscle-strengthening)

-"adults should also do muscle-strengthening activities that are moderate or high intensity and involve all major muscle groups on 2 or more days a week, as these activities provide additional health benefits."

PAG Note (Physical Inactivity)

-"all adults should avoid inactivity. Some physical activity is better than none, and adults who participate in any amount of physical activity gain some health benefits"

PAG Note (Special Populations)

-"the protective value of a medical consultation for persons with or without chronic diseases who are interested in increasing their physical activity level is not established - not necessary to consult health care provider prior to PA (although encourages), especially if increase gradually over time and remain asymptomatic

Substantial Health Benefits (guidelines)

-Minimum Intensity: Moderate - a person who does only light-intensity activity is regarded to be inactive -Minimum Duration: 10 min - episodes of 10 minutes or longer improve aerobic fitness and some biomarkers - unknown if benefits of one 30 minute bout are exactly the same as from three 10 minute bouts -Minimum Frequency: 3 days/wk - there is insufficient evidence to say that the health benefits are any different from : -50 min/day on 3 days/wk = 150 min -30 min/day on 5 days/wk = 150 min - the 30 min/day x 5 days/wk guideline may be too specific, but still ok to follow - guidelines suggest 3 days/wk as minimum frequency -know that 3 days/wk produces health benefits -concern about injury risk with 150 min from only 1 or 2 days/wk -most people spread the activity throughout the week

PAG (adults)

-ages 18-64 1.) Avoid inactivity 2.) Substantial health benefits from medium amounts of aerobic activity 3.) More health benefits from high amounts of aerobic activity 4.) Muscle-strengthening activities provide additional health benefits -for substantial health benefits, adults should accumulate: - at least 150 minutes (2.5 hours) a week of moderate-intensity aerobic activity - 75 minutes (1.25 hours) a week of vigorous-intensity aerobic activity - an equivalent combination of moderate- and vigorous- intensity aerobic activity

PAG (Children and Adolescents)

-ages 6-17 -60+ minutes of PA daily - most of the 60+min/day should be moderate-vigorous intensity aerobic PA - include muscle-strengthening PA and bone-strengthening PA at least 3d/wk (as part of the 60+min rec) -encourage participation in physical activities that are: - age appropriate, enjoyable, and offer variety -as opposed to adults, no choice on frequency -unstructured play can meet guidelines -requires some vigorous intensity activity (at least 3x/wk) - mod-intensity PA alone not sufficient -insufficient data to specify exact amounts/ranges of vigorous aerobic, muscle and bone strengthening -as children age, structured activity becomes more appropriate way to get PA -emphasis on variety of activities reflects attention to: - importance of skill development - reducing overuse injuries - fun/adherence -PA also recommended for children with disabilities

PAG (Older Adults)

-ages 65+ -same as for adults, but with 4 additional, age-specific guidelines 5.) For adults who cannot do 150 min/week -"when older adults cannot do 150 minutes of mod-int aerobic activity a week because of chronic conditions, they should be as physically active as their abilities and conditions allow." 6.) Balance exercise -" older adults should do exercises that maintain or improve balance if they are at risk of falling." 7.) Use "relative intensity" to determine the level of effort 8.) Chronic conditions and injury risk -"older adults with chronic conditions should understand whether and how their condition affect their ability to do regular physical activity safely."

Monitors (PA measurement: objective)

-assume mathematical relation between measurements and PA -many can measure quantity and intensity -recent tech advances make devices more practical (objectivity assess minutes spend in different intensities) -Heart Rate Telemetry (HR monitors) -Pedometers (Motion sensor) -Accelerometers (Motion Sensor)

Direct Observation (criterion)

-considered to be the "gold standard" of assessing PA -watching, recording, and scoring people PA within specific settings for a set period of time -can collect FITT -common form of youth-based assessment

Doubly-Labeled Water (criterion)

-considered to be the "gold standard" of assessing total EE -requires ingestion of known amounts of hydrogen and oxygen isotopes -EE calculated based on the difference between rates of loss of isotopes over time (how much has been metabolized) -practical through the lifespan

Subjective Advantages

-easy to use and score -cost-effective (inexpensive) -relatively short in duration (administered quickly) -suitable for both individuals and groups -can be quantitative and qualitative -effective indicants of which people are more/less active

Flexibility

-flexibility activities are acceptable and recommended, but... - minimal, if any, health benefits - insufficient evidence that activities like stretching reduce injury risk - flexibility activities by themselves do not count toward meeting guidelines -usually part of exercise programs/an important component of fitness -people need sufficient flexibility to be active -activities like stretching can increase flexibility

MVPA

-moderate to vigorous physical activity ≥24 Units: Active (Substantial Benefits) 14-23 Units: Moderately Active (Some Benefits) <14 Units: Insufficiently Active (Less Substantial/Low Benefits)

Self-Report (PA measurement: subjective)

-most often used in population-based research -assumed to assess indicators of "usual" PA -numerous methods available -may vary in length of recall EXAMPLES: -Logs and Diaries (real-time/recall) -Interview- and Self-Administered Surveys/Questionnaire (recall only)

Physical Activity Guidelines (PAG)

-not exercise guidelines -the federal government published comprehensive physical activity guidelines for Americans for the first time in 2008

Heart Rate Telemetry (HR monitor)

-objective -records BPM during activity, provides average BPM following activity -strong association between HR and EE (energy expenditure)

Pedometers (motion sensor)

-objective -typically worn on the hip -records number of daily steps by responding to vertical forces -same models are more sophisticated -GOAL: 10,000 steps/day (5 miles a day)

Accelerometers (motion sensor)

-objective -worn around waist or wrists -tri-axial (X, Y, and Z planes) -records body motion over time -provides detain on F, I, Time

Objective Limitations

-often not cost-effective (particularly for large groups) -immediate feedback may or may not be provided -evidence of potential to promote behavior change is equivocal -may not be able to ID type of PA -may not collect water-based PAs -potential discomfort or annoyance

Special Populations

-persons with disabilities -adults with select chronic conditions -women during pregnancy and the postpartum period -2018 Update: increased focus on ethnicity and race -age-specific guidelines are essentially the same - regular PA provides health benefits - type and amount determined by person's ability and the severity of health condition -understands how unique conditions affect ability -if unable, adapt program to match abilities

Godin Leisure Time Exercise Questionnaire (GLTEQ)

-proposed by Godin and Shephard (1985) -self-report measure which assesses the frequency of mild, moderate, and strenuous PA done for more than 15 minutes during a 7-day period -simple and easy to use; does not require high self-reporting skills -amongst the most popular and utilized self-report PA assessments -PA vs. Exercise? -for health contributions, focus on frequencies of moderate and strenuous activities -Total PA = 20 -MVPA = 20

Surveys/Questionnaire (Interview and Self-Administered)

-recall only -subjective self-report measurement -collects info about various aspects of PA -often domain-specific

Objective Advantages

-small, light weights, non-intrusive -easy to administer -avoids biases and inaccuracies -useful in a variety of settings -records in real-time -quick and easy data collection -strong link to energy expenditure (EE)

Subjective Limitations

-social desirability (bias) -memory-related issues -immediacy/recency -familiarity of terminology -may not be transferrable among populations -highly variable and questionable accuracy - all associated with varying degrees of error

Logs and Diaries (real-time/recall)

-subjective self-report measurement -document daily activity level -record detained info about FITT

Muscle-Strengthening Guidelines

-target major muscle groups - legs, hips, back, chest, abdomen, shoulders, arms -requires moderate to high level of intensity - relatively few repetitions (8-12) - 1 set sufficient -at least 2 days a week - insufficient data to comment on whether these should be non-consecutive days, or whether there is upper limit to days/week