Week 4 Lecture Slides: Physical Activity and Exercise PDF

Week 4 – Physical activity and Exercise What we’re going to cover today • Key terms/distinctions • Benefits • Guidelines • Rates and trends • Physical activity strategies and plans • Exercise addiction Key terms… What is physical activity? “Any bodily movement produced by the skeletal muscles...

Week 4 – Physical activity and Exercise What we’re going to cover today • Key terms/distinctions • Benefits • Guidelines • Rates and trends • Physical activity strategies and plans • Exercise addiction Key terms… What is physical activity? “Any bodily movement produced by the skeletal muscles that results in energy expenditure” (Caspersen et al., 1985, p.129) ØWalking the dog ØGardening ØHousework ØWalking to the shops And… Exercise “Planned, structured, and repetitive bodily movement done to improve or maintain one or more components of physical fitness” (Caspersen et al., 1985, p.129) Exercise is a subcategory of physical activity and includes: ØExercise classes ØGoing for a walk/run/cycle/swim ØLifting weights in the gym • So, not all physical activity is exercise, but all exercise is physical activity. 5 Major components of physical fitness (American College of Sports Medicine, 2018) • Muscular Strength – the ability to carry out work against a resistance. • Muscular Endurance – the ability to repeat a series of muscle contractions without fatiguing. • Cardiovascular Endurance – aerobic fitness/stamina, the ability to exercise continuously for extended periods without tiring. • Flexibility – the capacity of a joint to move through its full range of motion. • Body Composition – refers primarily to the distribution of muscle and fat in the body. Different types of exercise help us build different aspects of our fitness… Types of Exercise Isometric Exercise ØInvolves contracting a muscle or group of muscles against an immoveable object (e.g., the ground). ØThe muscle doesn't noticeably change length and the affected joint doesn't move. ØCan help maintain strength. Isotonic Exercise ØMovement that requires muscles to resist weight over a range of motion. ØRequires the muscles to change length and the affected joint(s) to move. ØBetter for building strength. Anaerobic Exercise ØAny exercise that breaks down glucose for energy without using oxygen. ØInvolves short, intensive bursts of effort. ØBetter for building strength. Aerobic Exercise ØAny exercise that requires a significant increase in oxygen usage over an extended period of time. ØRelies on energy stored in your body from carbs, protein, fat, and the oxygen you breathe. ØBetter for building muscular and cardiovascular endurance. “Step right up! It's the miracle cure we've all been waiting for.” (NHS, 2021) Physiological benefits of physical activity Reduced risk of non-communicable diseases: • Heart/Cardiovascular disease • Stroke • Certain types of cancer • Type 2 diabetes. • Osteoporosis (e.g., see Biddle et al., 2015; Brown & Gilmore, 2020; Reiner et al., 2013) Physical activity as a prevention for physical health problems Physical illness Level of evidence Impact of physical activity Coronary heart disease High Strong Stroke High Moderate Type 2 diabetes High Strong Osteoporosis High Strong Lower back pain Medium Weak Colon cancer High Strong Rectal cancer Medium No effect Breast cancer High Moderate Lung cancer Low Moderate Prostate cancer Medium Equivocal Endometrial cancer Low Weak Adapted from Department of Health (2004); Ogden (2019) COVID-19 protection – Sallis et al (2021) • Identified 44,440 adults diagnosed with COVID-19 between 1 Jan 2020 and 21 October 2020. • Grouped participants into 3 categories: consistently inactive, doing some physical activity, and meeting physical activity guidelines. • Results showed that, compared to those that were consistently inactive, those doing some physical activity and those meeting physical activity guidelines were at reduced risk of hospitalisation, admittance to ICU, and death. ØSpecifically, compared with those meeting physical activity guidelines, inactive people were 2.26 times more likely to be admitted to the hospital, 1.73 times more likely to need ICU care, and 2.49 times more likely to die. Protection against other infectious/communicable diseases – Chastin et al (2021) • Systematic review and meta-analysis of prospective studies and RCTs examining association between physical activity and immune parameters + immune response to vaccination. • In physical activity intervention studies, participants in intervention groups (versus controls) experienced increased: ØCD4 cell counts – play a key role in immunosurveillance (i.e., monitoring for pathogens). ØSalivary immunoglobulin IgA concentration – the first line of defence against pathogens. ØHigher antibody titres after receiving vaccinations – i.e., physical activity interventions increased the potency of the vaccination. Falls prevention World Health Organization (2021) • An estimated 684,000 fatal falls occur globally each year. • 37.3 million falls occur each year that are severe enough for the person to require medical attention. • Most among people aged >60. Australian and New Zealand Falls Prevention Society (2022) • Hip fractures a particular worry. Elderly people recover slowly from hip fractures and are vulnerable to post-operative and bed rest complications. • In around 25% cases, hip fractures result in death. Of those who survive, around one third never regain complete mobility. • After falling, 48% of older people report a fear of falling and 25% report curtailing activities. Inactivity during hospitalisation disastrous for physical function in older adults. • Over 30% of older adults leave hospital unable to do at least one activity of daily living they could do independently beforehand. • But a recent meta-analysis found that just 25 minutes of slow walking a day is enough to improve physical function (i.e., offset some of these risks) in older adults (GallardoGomez et al., 2023) Better tolerance to heat • Based on longitudinal evidence, researchers have estimated that children have up to 30% lower aerobic fitness than their parents did at a similar age (see Tomkinson et al., 2003; Morrison, 2022). • Morrison (2022) argues that younger generations are going to be less able to tolerate the hotter temperatures and periods of extreme heat that is going to become more common due to climate change. Psychological benefits of physical activity • Reduces anxiety. • Buffers against stress, allowing your body to better manage the feeling of stress, and your mind to process it better. • Increases cognitive functioning, including helping slow the progression of Alzheimer’s. • Improved mood and feelings of pleasure – sometimes… (e.g., see Lind et al., 2008; Rolland et al., 2008; Parfitt et al., 2006; Stephen et al., 2017) Parfitt et al. (2006) – Feeling scale (FS) responses of sedentary peple during exercise in below-lactate, above-lactate and self-selected conditions. FS scored on scale from -5 (very bad) to 5 (very good) Source: https://bpspsychub.onlinelibrary.wiley.com/doi/fu ll/10.1348/135910705X43606 Physical activity and depression In a recent meta-analysis of prospective cohort studies examining the link between physical activity and depression, Pearce et al. (2022) found: • Relative to adults reporting no activity, those accumulating half the recommended volume of physical activity had an 18% lower risk of depression. • Adults accumulating the recommended volume of physical activity hours per week had a 25% lower risk of depression than inactive people. • Estimated that, if less active adults had achieved the current physical activity recommendations, 11.5% of depression cases could have been prevented. Physical activity and depression • Rebar et al. (2015) – “Physical activity reduced depression by a medium effect… findings represent a comprehensive body of highquality evidence that physical activity reduces depression” • Dishman et al. (2021) – “Customary and increasing levels of moderate-to-vigorous physical activity in observational studies are inversely associated with incident depression and the onset of subclinical depressive symptoms” • Schuch and Stubbs (2019) – “a robust body of evidence from randomized controlled trials demonstrates that exercise is effective in treating depression” Mechanisms • Positive psychosocial changes (e.g., increased self-esteem and selfefficacy). • Biological adaptations that are linked to lower levels of depression. Specifically, positive changes in: ØBrain anatomy (e.g., increased hippocampal volume). ØMarkers of inflammation (e.g., reduced interleukin-6 levels) and oxidative stress (e. g., reduced thiobarbituric acid reactive substances serum levels). (e.g., see Eyre et al., 2013; Kandola et al., 2019; Lavebratt et al., 2017; Schuch et al., 2016) The benefits are not just from the activity itself… Stevens et al. (2021), Social Science & Medicine, Study 1 Indirect effects: Through loneliness: β = − .04, CI [-0.06, − 0.02], SE = 0.01. (significant) Through physical activity: β = − .08, CI [-0.10, − 0.06], SE = 0.01. (significant) Direct effects • Participants who belonged to a sport or exercise group at Wave 7 had a 11.8% chance of scoring above the clinical cut-off for depression at Wave 9. • Non-sport or exercise group members at Wave 7 had a 20.4% chance of scoring above this cut-off at Wave 9. How much should we do? Australian Government (Department of Health) guidelines state that adults aged 18-64 should: • Each week do either: Ø2.5+ hours of moderate intensity physical activity. Ø1.25+ hours of vigorous intensity physical activity. ØOr an equivalent combination of moderate and vigorous activities. • Include muscle-strengthening activities on at least 2 days each week. ØE.g., Push-ups, pull-ups, squats, lunges, lifting weights. How much should we do? Australian Government (Department of Health) guidelines state that children aged 5-17 should: • Do at least 60 minutes of moderate to vigorous physical activity that makes the heart beat faster each day. • Include muscle and bone strengthening activities within this on at least 3 days per week. ØE.g., running, climbing, swinging on monkey bars, push ups, sit-ups, lifting weights, yoga. • Do several hours of various light physical activities each day. ØE.g., Walking to school, walk the dog, go to the park, play at school. How much should we do? Australian Government (Department of Health) guidelines state that older adults aged 65+ should: • Do at least 30 minutes of moderate intensity physical activity on most, preferably all, days. ØE.g., Brisk walking, swimming, golf, cycling. • Try to incorporate different types of activities during the week. ØE.g., Strength-based activities, flexibility activities, balancing activities. How much do we do? • Self-report data suggest 27.5% of adults worldwide are insufficiently active (Guthold et al., 2018). • 65% of Australian adults are insufficiently active (Australian Institute of Health and Welfare [AIHW], 2020). • Accelerometer data suggest inactivity rates even higher – >90% of Americans insufficiently active (Tucker et al., 2011). ØWe are in a physical inactivity ‘pandemic’ (Kohl et al., 2012; Sallis et al., 2016) Are things getting any better? Prevalence of insufficient physical activity among Australian adults over time 80 70 Percentage 60 of Australian 50 adults not 40 meeting PA 30 guidelines 20 10 0 2011-12 2014-15 2017-18 Source: AIHW analysis of the ABS National Health survey 2019, 2016, 2014. 40 35 30 25 20 15 10 5 0 Ja n06 Ja n07 Ja n08 Ja n09 Ja n10 Ja n11 Ja n12 Ja n13 Ja n14 Ja n15 Percentage Once a week participation in sport in the UK Time period https://www.bbc.com/sport/commonwealth-games/62486344 https://www.bbc.com/sport/olympics/62299772 Source: Sport England Active People Survey Steady trends but individual volatility? • Weed (see Hagger & Weed, 2019) points to data suggesting that, each year: Ø40% consistently do no sport Ø20% maintain their participation Ø20% of the population drop out of or do less sport Ø20% taking up or do more sport Adherence and maintenance is a problem… Average gym visits in first 12 months of membership (N=1726) (Rand et al., 2020) 8 7 6 5 4 3 2 1 12 on th 11 M M on th 10 9 on th M on th 8 M on th 7 M on th 6 M on th 5 M on th 4 M M on th 3 2 on th M on th M M on th 1 0 McEwan et al (2022) – ‘What happens when the party’s over?’ • Meta analysis of 39 interventions that measured physical activity at baseline, post a physical activity intervention, and at a follow-up timepoint. Significant increases in physical activity from baseline to postintervention (d = 0.46). Significant improvements in physical activity found from baseline to follow-up (d = 0.32). Significant decreases from post-intervention to follow-up (d = −0.18). d = .46 Baseline Post-intervention d = .32 d = -.18 Follow-up • The positive effects from baseline to post-intervention and the negative effects from post-intervention to follow-up were more pronounced as the length of time between assessments increased. i.e., Ø The longer the physical activity intervention the greater the initial positive impact on behaviour. Ø But the longer the time between the intervention and the follow up the more the impact of the intervention had worn off. Who is active? Activity levels by age and gender Source: Health survey for England (2016) Agestandardised activity levels, by Index of Multiple Deprivation (IMD) Source: Health survey for England (2016) Physical activity rates among Indigenous Australian adults compared to Non-Indigenous Australian adults • Data collected by the ABS in 2018/19 suggested that just 12% of indigenous adults met physical activity guidelines. • Steady at around 35% in the Australian population as a whole (AIHW, 2020). • In 2012—the last time a direct comparison was carried out between Indigenous and Non-Indigenous Australians—the physical activity ‘gap’ among adults was 18%. ØSo this seems to have widened to around 23%. Indigenous adults’ (18+) reported levels of physical activity and strength or toning activities, by age group and sex, non-remote areas, 2018–19 Burden/consequences Each year, physical inactivity directly contributes to: • 5.3 million deaths (Lee et al., 2012). • USD$53.8 billion (≈AUD$83) in health care costs (Ding et al., 2016). • £7.4 billion per year in the UK alone (Public Health England, 2014). All of this has prompted the WHO (2013, 2018) to launch a plan targeting: • A 10% reduction in physical inactivity by 2025 • A 15% reduction in physical inactivity by 2030 How much do we need to do to get some benefits? • Anything is better than nothing! • The dose-response relationship between how much physical activity you do and the level of benefits you get is non-linear. • Those who are least active get the most benefit from increasing their physical activity. Ekelund et al (2019) https://www.bmj.com/content/366/bmj.l4570.full https://www.bmj.com/content/366/bmj.l4570.full dos Santos et al (2022) – Can we get equivalent benefits by being a ‘Weekend Warrior’? • 350,978 participants self-reported their physical activity as part of the US National Health Interview survey between 1997 and 2013. • Participants’ National Death Index records checked on December 31, 2015. • Compared with physically inactive participants, both ‘regularly active’ participants (who completed ³ 3 sessions/wk) and ‘weekend warriors’ (who completed 1-2 sessions/wk) were at reduced risk of all cause mortality and mortality due to heart disease and cancer. • Given the same amount of total moderate-vigorous physical activity, ‘weekend warrior’ participants had similar all-cause and cause-specific mortality rates as ‘regularly active’ participants. Feng et al (2023) – Does when we do physical activity during the day matter? • 92,139 UK Biobank participants. • Physical activity assessed via accelerometers (worn for a week). • Dependent variables – all-cause and cause-specific mortality. • Median follow-up of 7 years. Results Controlling for other key predictors (e.g., age, smoking status, alcohol intake)… • Participants who completed >50% of daily moderate-to-vigorous intensity physical activity (MVPA) either (a) between approximately midday and afternoon (11:00-17:00), or (b) at a mixture of times had lower risks of all-cause and cardiovascular disease mortality than those who completed >50% of daily MVPA during the morning (05:0011:00). • Completing >50% of daily MVPA in the evening (17:00-24:00) didn’t predict lower risks of all-cause and cardiovascular disease mortality than completing >50% of daily MVPA in the morning. Steps per day and health – Sheng et al (2021) All cause mortality Cardiovascular disease Source: https://www.sciencedirect.com/science/article/pii/S2095254621001010 All cause mortality Paluch et al (2022) How useful are steps per day? • Simple and easy to interpret measure. • Readily trackable – phones, watches etc. What have we tried to do to increase physical activity? —Strategies and plans https://apps.who.int/iris/bitst ream/handle/10665/272722/ 9789241514187-eng.pdf WHO Action Plan • A set of specific policy actions to guide member states to accelerate and scale activities towards achieving increased levels of physical activity. • Policy actions grouped under 4 key objectives: ØCreate active societies ØCreate active environments ØCreate active people ØCreate active systems Create active societies Policy actions that aim to: “Create positive social norms and attitudes and a paradigm shift in all of society by enhancing knowledge and understanding of, and appreciation for, the multiple benefits of regular physical activity, according to ability and at all ages.” Create active environments Policy actions that address the need: “To create supportive spaces and places that promote and safeguard the rights of all people, of all ages and abilities, to have equitable access to safe places and spaces in their cities and communities in which they can engage in regular physical activity.” Create active people Policy actions that: “Outline the multiple settings in which an increase in programmes and opportunities can help people of all ages and abilities to engage in regular physical activity as individuals, families and communities.” Create active systems Policy actions that: “Outline the investments needed to strengthen the systems necessary to implement effective and coordinated international, national and subnational action to increase physical activity and reduce sedentary behaviour. These actions address governance, leadership, multisectoral partnerships, workforce capabilities, advocacy, information systems and financing mechanisms across all relevant sectors.” The plan outlines 4-6 proposed broad ‘actions’ in relation to each area and several specific actions that it recommends should be carried out by member states, the WHO, and stakeholders. Action 1.3 for creating active societies “Implement regular mass participation initiatives in public spaces, engaging entire communities, to provide free access to enjoyable and affordable, socially and culturally-appropriate experiences of physical activity.” To achieve this action, it argues that… Member states should: “Implement free, universally accessible, whole-of-community events that provide opportunities to be active in local public spaces.” WHO should: “Partner with stakeholders to support the development of tools and resources to assist Member States in implementing mass participation initiatives in public open, green and blue spaces.” Stakeholders should: “Research and development agencies and academics should partner to conduct evaluations of mass participation events to assess impact, including economic impact.” • Approximately 2000 events worldwide each week • Approximately 470 events each week in Australia. Member states should: “Implement free, universally accessible, whole-of-community events that provide opportunities to be active in local public spaces.” – 22 different countries doing this. WHO should: “Partner with stakeholders to support the development of tools and resources to assist Member States in implementing mass participation initiatives in public open, green and blue spaces.” – the WHO don’t have a direct involvement, but parkrun do have relevant supporting partners (e.g., the world athletics governing body). Stakeholders should: “Research and development agencies and academics should partner to conduct evaluations of mass participation events to assess impact, including economic impact.” – increasingly common context for research. Grunseit et al. (2020) • Review of studies examining participation in, and benefits of, parkrun. • Participants showed sustained improvements in fitness, physical activity levels, and body mass index with a dose–response effect with participation frequency. • Qualitative data showed parkrun’s location in pleasant environments with opportunities for informal social interaction engages priority groups such as individuals with mental health issues, women, and children. ‘State of life’ (2021) report concluded: • UK parkrun generates at least £150 million in health and wellbeing impact each year. • A social return on investment of £30 for every £1 spent. Exercise addiction Exercise addiction Some people can reach a stage of viewing exercise as “necessary” and demonstrate the same behaviours/symptoms as people who are addicted to other behaviours (e.g., smoking, alcohol): • Withdrawal symptoms. • Disturbed psychological functioning. • Engaging in the behaviour despite medical contraindications (e.g., while injured). • Interference with relationships or work. Berczik et al. (2012), Landolfi (2012) Exercise addiction (dependence) “describes excessive exercise which impacts a person’s life and reflects a feeling of being out of control.” (Ogden, 2019, p.63) There are problems with this definition though (Ogden, 2019): • Assumes there is a ‘normal’ life (i.e., involving work, family, friends etc.) and that a behaviour that interferes with this is harmful. • Someone who exercises ‘excessively’ might feel perfectly in control of their behaviour as long as their life allows them to exercise to the level that they need to. • The term ‘excessive’ is also problematic – depends on social norms as a guide for how we should distribute our time. Prevalence of exercise addiction • Seems to be relatively rare in the general population. Ø0.3–0.5% of the adult general population in a representative (Hungarian) sample (Monok et al., 2012). • Researchers have suggested a wide range of prevalence rates in athletes: Ø25% of female and 26% of male runners (Slay et al., 1998) Ø52% of triathletes (Braydon & Lindner, 2002) Ø3.2% of ultra-marathoners (Allegre et al., 2007) Causes of exercise addiction A disease model • Exercise behaviours become an addiction because exercise generates endorphins and therefore feelings of pleasure/euphoria – e.g., a ‘runners high’. • When the endorphins decay people want those feelings again. • Exercise can improve mood but, after a while, this state deteriorates, and people can experience withdrawal symptoms. • They therefore exercise to reverse this withdrawal process. • People can become tolerant to their level of exercise and therefore need to exercise more to experience the same feelings. A social learning model • Reinforcement: Stress reduction, increased energy, and improved mood, body shape, and body image can be reinforcing and lead people to want to engage in the behaviour more. Changes in body shape can also be reinforced through compliments from others. • Modelling: E.g., if people start socialising in groups of other ‘excessive’ exercisers (e.g., bodybuilders, running clubs). • Associative learning: Paired with cues such as social groups (e.g., jogging clubs), being in fresh air, feeling stressed, unattractive, or fat. These can become cues for further exercise. Consequences of exercise addiction • Physical injuries (e.g., in knees, ankles, back) that get exacerbated because people continue exercising rather than letting them recover. • Negative effects on interpersonal relationships – e.g., absent parent, neglecting family responsibilities. • Detrimental to anxiety and depression in the long-term if a person becomes dependent on exercise to manage their well-being. Questions? Readings Essential reading for your labs: Landolfi, E. (2013). Exercise addiction. Sports Medicine, 43(2), 111-119. Optional (but interesting!): Milton, K., Cavill, N., Chalkley, A., Foster, C., Gomersall, S., Hagstromer, M., Kelly, P., Kolbe-Alexander, T., Mair, J., McLaughlin, M., Nobles, J., Reece, L., Shilton, T., Smith, B. J., & Schipperijn, J. (2021). Eight investments that work for physical activity. Journal of Physical Activity and Health, 18(6), 625-630. Next week • No live lecture. • Recording will be available on Wattle from later this week. • Watch this as early as possible to give yourself maximum time to prepare for your labs.