exercise for health

see also:

• nature exposure and benefits to health
• atherosclerosis and primary prevention
• obesity and weight management
• frailty
• Am Heart Association recommendations for exercise in adults

• regular exercise is critical to maintain cardiovascular health, reduce chronic disease risks including cancer and improve mental health
• ideally there should be a variety of exercise types undertaken regularly such as walking, walking up hills or stairs, and resistance training with weights or similar
• care must be taken though to avoid injury from exercise which can then make exercise levels difficult to achieve
• unfortunately exercise appears to have minimal direct benefits to osteoarthritis¹⁾ but maintaining muscle and bone mass are still important reasons to exercise

• affective responses vary as to how individuals enjoy or not enjoy these activities and this may be partly genetic, partly due to responses to exercise induced production of endocannabinoids
• genetic factors can also significantly cause variance in response to types of exercise regimes

• the V⁢O2⁢max, is a key index of cardiovascular and cardiorespiratory fitness and an increase in V⁢O2⁢max, improves the ability of the body to both supply and utilise oxygen which prolongs the time to exhaustion and the ability to sustain aerobic exercise for longer periods of time, at higher intensities such as walking up many flights of stairs
• there are many health advantages to maintaining at least a moderate level of aerobic fitness
• cardiovascular fitness requires aerobic exercise rather than resistance exercise but high intensity aerobic exercise should only be newly undertaken in those over 35yrs after consideration of coronary risks to reduce sudden deaths
  • timing of exercise may be important as cardiovascular events are more likely to occur soon after wakening²⁾
  • the 13 year prospective Isfahan Cohort Study in Iran suggested that only occupational physical activity reduced mortality, not leisure time activity - but this does not seem to be logical to me and I would think it needs substantive validation from more studies³⁾
  • a prospective 2026 Australian study⁴⁾ of 58,000 women suggests that women who moderate exertion exercise 150min/wk (eg. 30 minutes of brisk walking five days a week) halve their mortality rates
  • a study published in 2026 suggests those who do 4% of total exercise as vigorous had 29% to 61% lower risk of all outcomes than those with 0% vigorous and any vigorous activity could potentially prevent 21.4% of CRD, 32.3% of dementia, and 20.3% of IMID cases relative to 0% vigorous⁵⁾
  • exercise at over 130MET-min/wk helps reduce steatohepatitis (fatty liver) with maximum effect seemingly attained by 850MET-min/wk⁶⁾
• the better the quality of chest and back skeletal muscle (with less fat) in middle age on CT scan - the lower the risk of heart attacks and 10 year mortality
  • for every 10-point increase in scan brightness, indicating better quality muscle with less fat in it, a person was calculated to be 31 percent less likely to have a heart attack. They were also 39 percent less likely to die in the 10 years after having the scan⁷⁾

• strength refers to the force that can be generated during a voluntary muscle contraction
• this is required for everyday tasks and mobility and is important in preventing chronic joint instability, sarcopenia / generalised muscle wasting and frailty
• resistance training is important
  • optimizing muscle mass and bone mass to reduce frailty and osteoporosis fracture risks needs resistance exercise
  • long term 2hrs of resistance training per week in women reduced cardiovascular and neurological mortality, no additional benefit was observed above 120 min/week, but the 2hr benefit was additive to benefits of aerobic training durations up to 45 MET-hours/week of aerobic activity⁸⁾

• anaerobic power is the ability of the neuromuscular system to produce the greatest possible action in a given time period and is needed for quick bursts explosive movements and agility

• this is needed to reduce osteoporosis particularly of the spine, pelvis and hips
• swimming and cycling are NOT regarded as weight-bearing exercises

• this is exercise undertaken as part of day to day activities such as house work, gardening, mowing the lawns, walking up stairs, etc
• those with a naturally fast gait cadence appear to have reduced mortality

• this is exercise performed at work such as with manual labourers

• exercise as part of a sports activity

• eg. regular jogging, swimming, cycling, weight lifting, gym work, training for a sport

Source: 2026: BMJ. Physical activity types, variety, and mortality: results from two prospective cohort studies

NB. MET is the metabolic rate for an activity / resting metabolic rate hence light walking is 2-2.5MET, brisk walking is 3.5-4.5MET, climbing stairs is 8-9MET, descending stairs is ~2.9MET, slow jogging 7-8MET, running at 11kph 11-12MET (faster can get to 20MET), cycling < 16kph 3-4MET 16-20kph 6-8MET, easy swimming laps 5-6MET, fast swimming laps 8-10MET;

• ideally an exercise regime should have a mix of activities, the safest and most beneficial appear to be walking and walking up hills or stairs
• it seems moderate weekly exercise of 90min/wk (eg. walking) is associated with nearly a 50% lower risk of AF recurrence following catheter ablation²¹⁾
• it seems that one can reverse years of adverse cardiac effects from long standing sedentary lifestyles in the middle age by adopting an exercise program with the following minimal levels:
  • it has to be something they have access to
  • it has to be something they enjoy
  • it has to be alternating impact and low impact, and each week:
    • at least one or two long sessions (1hr) of brisk walking, dancing or sport such as tennis
    • at least one or two high intensity aerobic sessions (20-30min) of walking up hills, etc.
    • at least two or three moderate exercise sessions which raise a sweat but not shortness of breath such as moderate walking
  • yoga or weight lifting do not improve cardiovascular fitness, but each have their own benefits and risks if not performed with care

• responses to various types of exercise varies significantly between individuals and much of this variance is due to genetic differences
  • a recent study suggests 72% of the variable response to strength changing is genetic while 44% of variance to aerobic training was genetic²²⁾

• dimethylguanidino valeric acid (DMVG), exercise and health
  • increasing exercise can lower levels of dimethylguanidino valeric acid (DMVG), a molecule in the blood linked to poor health outcomes BUT those with “more room to improve” – actually saw less benefit from exercise than people with lower baseline levels of DMVG – those in better health to begin with. DMGV was associated with adverse metabolic risk even in very young individuals free of overt disease. DMGV levels may identify individuals who are less responsive to the metabolic health benefits of endurance exercise training and may require additional therapies beyond guideline-directed exercise to improve their metabolic health. ²³⁾
• the α-actinin-3 protein gene (ACTN3)
  • the α-actinin-3 protein is found in muscles important for explosive activities such as sprinting but is also for the androgen receptor in muscle tissue in both men and women and response to testosterone - at least 7 genes tat drive this effect depend on the α-actinin-3 protein for proper expression ²⁴⁾
  • one in five people lack this protein due to inheriting two copies of the null variant (577X) in the ACTN3 gene
    • a common null polymorphism in ACTN3 (R577X) arose in modern humans and underwent positive selection ~10 to 15,000 years ago
    • among the elderly, α-actinin-3 deficiency is associated with significantly lower strength and higher frailty scores in an elderly Chinese population
• myokines
  • cytokines or other small proteins (~5–20 kDa) and proteoglycan peptides that are produced and released by skeletal muscle cells (muscle fibers) in response to muscular contractions
  • receptors for myokines are found on muscle, fat, liver, pancreas, bone, heart, immune, and brain cells
  • they are involved in exercise-associated metabolic changes, as well as in the metabolic changes following training adaptation
  • they also participate in tissue regeneration and repair, maintenance of healthy bodily functioning, immunomodulation; and cell signaling, expression and differentiation
  • eg, myostatin, irisin
  • L-β-aminoisobutyric acid (L-BAIBA)
    • the metabokine molecule L-β-aminoisobutyric acid (L-BAIBA) is released during exercise and is required for muscle to adapt to exercise, making it stronger and protecting against damage and weakness. It regulates muscle metabolism, morphology and function via peroxisome proliferator-activated receptor delta (PPARδ) and regulates human myotube fibertype and differentiation markers through Mas-related G-protein coupled receptor D. In humans, plasma L-BAIBA correlates with aerobic fitness and increases with endurance exercise training. ²⁵⁾
    • also protects muscle from damage that occurs in type 2 diabetes which can limit a person's quality of life, such as loss of muscle and strength, and impaired metabolism²⁶⁾
• mechanisms in resistance training
  • intense resistance exercise induces acute myofibrillar damage and activates a specialized repair system that recognizes damaged muscle components and targets them for removal. At the same time, this repair machinery promotes the synthesis of new contractile proteins, replacing those that have been damaged. This coordinated process preserves and reinforces the muscle's contractile apparatus.²⁷⁾
    • regulation mainly affects the protein network linked to the muscle maintenance protein BAG3, which includes mechanosensory proteins, small heat shock proteins, and a lipid droplet associated protein
    • all network components exhibit altered phosphorylation and increased cytoskeletal association after damaging resistance exercise and network components cooperate to recognize strained skeletal muscle structures and mediate their degradation through chaperone-assisted selective autophagy (CASA)
• extreme exercise such as marathon running appears to activate the endocannabinoid system which may contribute to their high
  • a 2015 study showed that the anxiety- and pain-reducing effects of running depend on cannabinoid receptors
  • a 2021 study involving 63 people demonstrated that the runner's high still occurs when the effects of endorphins are pharmacologically blocked
  • a 2026 study showed that the endocannabinoid anandamide (AEA) does not only increases at the beginning of a run. Its concentration continues to rise over the course of an entire marathon, and levels are still elevated even 45 minutes later, and blood levels of a second endocannabinoid, 2-AG, also increased.²⁸⁾