physical activity in disease prevention
Research shows inactivity is a primary risk factor for diseases like cardiovascular disease, diabetes, and certain cancers.
Primary Prevention: Regular activity prevents diseases before they occur.
Secondary Prevention: Helps manage and reduce progression of pre-existing conditions.
physiological response to physical activity
Homeostasis and Cellular Response:
Physical activity stimulates widespread systemic responses to maintain oxygenation and pH balance.
Key Systems:
- Cardiovascular: Increases blood flow and oxygen delivery.
- Respiratory: Enhances oxygen uptake and CO₂ expulsion.
- Muscular: Uses glycogen and fat as fuel; clears metabolic waste.
Acute Changes:
During exercise, skeletal muscles drive these adaptations to support energy production.
cellular adaptation and protein synthesis in physical exercise
Gene Transcription and Protein Changes: Physical activity promotes protein synthesis, particularly in mitochondria and muscle cells.
Muscle Adaptations:
- Increased contractile efficiency and mitochondrial density.
- Enhanced glucose uptake with GLUT-4 protein activation.
Long-Term Benefits:
These adaptations reduce chronic disease risk by improving cellular
resilience and efficiency.
physical activity or pharmacotherapy- comparative effectiveness
exercise is about effects as drugs in terms of its mortality benefits in the secondary prevention of coronary heart disease and diabetes, stroke rehabilitation and heart failure
physical activity effects on cognitive decline and brain health
Reduced Cognitive Decline:
Regular exercise reduces the risk of dementia and cognitive impairments.
Mechanisms:
- Increases neurotrophic factors (e.g., BDNF, IGF-1), which support brain
health.
- Enhances blood flow to the brain, slowing atherosclerosis and promoting
neuroplasticity.
Statistic: A meta-analysis revealed a 40% reduced risk of cognitive decline in
physically active individuals.
impacts of physical exercise on hypertension and cardiovascular benefits
Blood Pressure Regulation:
Physical activity lowers systolic and diastolic blood pressure by increasing
nitric oxide (NO) production.
Mechanisms:
Improves vascular elasticity and endothelial function, reducing peripheral
vascular resistance.
Research Insight:
27 RCTs show regular aerobic exercise reduces blood pressure by an
average of 11/5 mmHg, especially in hypertensive individuals.
physical activity and diabetes prevention
Type 2 Diabetes Risk Reduction:
Physical activity improves insulin sensitivity and reduces blood glucose levels.
Mechanisms:
GLUT-4 transporters increase glucose uptake in muscle cells, reducing blood glucose and HbA1c.
Comparative Efficacy:
Physical activity is as effective as medication for type 2 diabetes management in mortality risk reduction.
exercise impacts on anxiety, depression and sleep
Reduces both state and trait anxiety, alleviates symptoms of depression, and improves
sleep quality.
Mechanisms:
Boosts serotonin, dopamine, and endorphin levels, enhancing mood and stress
resilience.
Key Statistics:
Over 30 minutes of daily physical activity can reduce depression risk by up to 50%.
Meta-analysis of 66 studies shows improved sleep latency and quality in active
individuals.
cancer prevention and physical activity
Cancer Risk Reduction:
Physical activity lowers risks for cancers like bladder, breast, and colon by 10-20%.
Mechanisms:
Enhances immune function, metabolic stress on tumor cells, and blood flow to affected areas.
Sedentary Risks: Sedentary behavior increases endometrial and
colon cancer risk by 20-35%.
physical exercise impact on arthritis and MSK health
Joint Health in Arthritis:
Exercise, especially low-impact activity, reduces joint pain and improves
function in osteoarthritis.
Mechanisms:
Dynamic compression during movement enhances cartilage health by counteracting inflammation.
Research Finding:
Physical activity reduces pain and improves physical function in adults
with knee and hip osteoarthritis.
physical activity impact on osteoporosis prevention and bone health
Bone Density and Osteoporosis:
Regular weight-bearing and resistance exercises increase bone mineral density.
Mechanotransduction:
Physical stress from activity stimulates bone cells, strengthening bone
microarchitecture.
Clinical Insight:
Increased physical activity lowers hip fracture risk and enhances balance, reducing fall-related injuries.
physical exercise impact on weight management and metabolic health
Weight Control:
Physical activity helps prevent weight gain and supports weight loss with caloric restriction.
Energy Balance:
Increases basal metabolic rate and fat oxidation, contributing to weight management.
Appetite Regulation:
High levels of physical activity align energy intake with expenditure, reducing
risk of overeating.
physical exercise impact on healthy aging and longevity
Aging and Independence:
Physical activity preserves muscle mass, reduces sarcopenia, and maintains mobility in older adults.
Mortality Reduction:
Active individuals have a 35% lower risk of all-cause mortality and longer telomere length.
Key Statistic: Meeting physical activity guidelines (150 minutes/week) is associated with up to a 19% reduction in mortality risk.
impact of physical activity and its benefits on social and psychosocial benefits
Mental and Social Well-being:
Physical activity improves self-esteem, reduces
stress, and enhances confidence and body image.
Community Engagement:
Group activities build cooperation, resilience, and
positive attitudes that translate into other life areas.
risks of physical activity
Overview:
Physical activity provides numerous health benefits, but risks exist, especially for untrained individuals or those resuming activity suddenly.
Importance: Though benefits outweigh risks, clinicians should carefully evaluate risks when prescribing physical activity.
Common Risks:
–>Most Common: Musculoskeletal injuries.
–>Less Common but Serious: Cardiac events (e.g., sudden cardiac arrest,
myocardial infarction).
MSK injuries; risk of physical activity
Types of Injuries:
Injuries can be acute (e.g., sprains, fractures) or due to overuse (e.g., tendinitis, stress fractures).
Examples: Cartilage tears, joint dislocations, bursitis, and tendinopathies.
Risk Factors:
- Higher frequency of minor injuries in active individuals.
- Severe injuries more likely in those who are typically sedentary and begin vigorous activity suddenly.
Special Case:
Rhabdomyolysis: Severe muscle breakdown after intense, prolonged activity (e.g., marathons).
Incidence: ~30 cases per 100,000 patient years.
cardiac risks from physical activity
Potential Cardiac Events:
Acute myocardial infarction, malignant arrhythmias, and sudden cardiac death.
Triggering Factors:
Sudden, intense activity in unaccustomed individuals can trigger these events.
Preventive Insight:
While intense activity has risks, regular physical activity overall reduces the
likelihood of cardiac events in most patients.
respiratory risks from physical activity
Exercise-Induced Bronchoconstriction (EIB):
- Description: Physical activity can cause bronchial constriction, with
asthma-like symptoms.
- Symptoms: Dyspnoea, chest tightness, wheezing, and cough.
Clinical Note:
- EIB often misdiagnosed due to its non-specific symptoms.
- Management may require tailored pre-exercise protocols for
individuals prone to EIB
heat-related risks from physical activity
Heat-Related Risks:
-Heat Stroke: Increased incidence in recent decades, second to cardiac events in sport- related deaths.
- Dehydration: Loss of fluids reduces blood volume, lowering blood pressure and sweat rate.
–>Symptoms: Weakness, fatigue, vomiting, and diarrhoea.
In-Built Protection Mechanisms:
The body can self-regulate to prevent overheating if individuals stop activity when needed.
Risk Factors for Heat Stroke:
Linked to factors like recent illness, genetic predispositions, and drug use, not just physical
exertion alone.
exercise counselling
The 5A’s framework (Ask, Advise,
Assess, Assist, Arrange)
ask: assess physical activity levels i.e. how often do exercise
advise: provide tailored advice, i.e. 150 min/wk
assess: readiness to change, identify barriers
assist: support behaviour change via exercise logs, fitness apps, regular check ins etc
arrange: follow ups
transtheoretical and health belief models of behaviour change
Transtheoretical Model: Describes stages of changefrom pre-contemplation to maintenance.
Health Belief Mmodel: Focuses on perceived severity, benefits, barriers, and self-efficacy in adopting healthy behaviours.
motivational interviewing for exercise counselling
Core Principles:
Express Empathy: Show understanding and acceptance.
Develop Discrepancy: Highlight the gap between current behaviour and
health goals.
Roll with Resistance: Avoid arguing; understand patient ambivalence.
Support Self-Efficacy: Encourage belief in the ability to change.
techniques:
Open-Ended Questions: Encourage detailed responses, e.g., “What are your
thoughts on increasing your activity?”
Reflective Listening: Paraphrase what the patient says to show understanding
and validate feelings.
Eliciting Change Talk: Use strategies like asking about the benefits of change
or past successes to evoke motivation (i.e. how might you feel if you were more active)
component of exercise rx
Type: Specific physical activity.
Dose: Amount or duration of exercise.
Frequency: How often.
Goal: Target outcomes for health.
