Health and well-being: when physical activity improves quality of life

IN BRIEF

• Physical activity includes any movement produced by skeletal muscles, not just organized sports.
• Observational evidence links inactivity to an increased risk of cardiovascular disease, type 2 diabetes, certain cancers, poorer mental health, and premature mortality.
• Benefits depend on dose, intensity, and context: even small increases in activity yield significant advantages for the population.
• The most robust data are observational or from meta-analyses; for some questions, experimental evidence is available (e.g., glycemic control), but methodological limitations require interpretive caution.

Abstract: what does science say?

Physical activity is defined as any movement produced by skeletal muscles that increases energy expenditure compared to rest. Numerous observational studies and meta-analyses show consistent associations: higher levels of activity are linked to lower probabilities of cardiovascular disease, diabetes, certain cancers, depression, and premature mortality. The dose-response relationship is non-linear: the greatest gain is achieved by moving from inactivity to moderate levels; further activity brings additional benefits but with a flattening curve. The advantages also depend on the distribution of movement over time, the type of activity, and individual characteristics (age, chronic conditions). Although there is experimental evidence for some outcomes (e.g., improved glycemic control), most estimates come from observational studies; for this reason, causal inferences require caution and contextual evaluation.

What do we mean by physical activity and how widespread is inactivity?

Physical activity refers to any bodily movement produced by skeletal muscles that results in an energy expenditure greater than resting levels: from walking, to climbing stairs, to practicing sports or structured training. This definition includes both deliberate activity (exercise, sports) and daily mobility and household chores.

In Europe and globally, surveys report a significant proportion of people who do not meet minimum recommendations (e.g., 150 minutes per week of moderate activity or 75 minutes of vigorous activity). Analyses of large series of surveys show that the prevalence of inactivity varies by sex and region: in some European areas, women have a higher percentage of inactivity than men [1].

This widespread inactivity has significant health and social consequences because reduced daily movement is associated with a higher incidence of chronic diseases and a substantial overall healthcare burden. Monitoring population activity levels is therefore a useful indicator for public prevention policies [1].

Why physical activity is relevant for cardiovascular prevention and general health

Physical activity is recognized as a factor that contributes substantially to the primary and secondary prevention of cardiovascular diseases: through improvements in blood pressure profile, metabolic profile, and functional capacity, it can reduce the risk of ischemic events and mortality related to heart disease [2].

European clinical guidelines emphasize the importance of promoting movement at both population and individual levels, integrating it into cardiovascular care and prevention pathways [3]. The literature shows plausible biological mechanisms (improved insulin sensitivity, anti-inflammatory effects, improved endothelial function) that explain the observed associations between activity and reduced cardiovascular risk [2].

However, it is important to distinguish between association and causality: much evidence comes from observational studies that document robust correlations but can be influenced by confounding factors or measurement bias. For some outcomes, such as improved blood pressure or glycemic control in people with diabetes, there is evidence from randomized clinical trials confirming the beneficial effects of exercise compared to no intervention [7][5].

When sport extends life

Meta-analyses and large cohorts show a dose-response relationship between recreational activity and mortality: even activity levels below recommendations produce significant reductions in the risk of death from all causes, with the greatest benefit for those who transition from inactivity to moderate activity. The benefit curve tends to flatten at higher activity levels, but in most analyses, it does not show a net increase in risk for those who are very active [4].

These results support the practical message that modest increases in activity within the population can have a great impact in terms of public health. However, there remains a need to contextualize the numbers to specific populations and to consider objective measures of activity when available, given that self-reported questionnaires can underestimate or overestimate exposure [4].

What this means in practice

For the general public, evidence suggests that any increase in daily movement can be beneficial: short walks, replacing car trips with cycling or walking, using stairs, and breaking up prolonged periods of sedentary behavior are actions that, distributed over time, contribute to overall health improvement. Even moderate-intensity activities performed regularly are associated with a reduced risk of many chronic diseases [4][6].

In individuals with type 2 diabetes or those at risk, structured exercise programs—aerobic, resistance, or combined—have shown measurable improvements in glycemia (reduction in HbA1c) and other metabolic indicators: these results come from controlled studies, but the most effective type of intervention depends on the individual context and the person's functional capabilities [5].

For cancer prevention, observed associations include risk reductions for various types of cancer; the strength of the evidence varies among cancers and does not imply that physical activity is a "treatment" but rather a risk reduction factor in the population [6].

In practical terms: perfect behavior is not necessary to obtain benefits. Small changes repeated over time add up; individual clinical indications must always take into account pre-existing conditions and the advice of a healthcare professional.

Limitations of the Evidence

It is essential to separate the different levels of evidence. Many results supporting the effect of physical activity on long-term outcomes come from prospective observational studies and meta-analyses of cohorts: these studies document strong associations but cannot, by themselves, establish definitive causality due to possible confounders, selection bias, and imprecise measurements of activity. For some outcomes (e.g., HbA1c in diabetes), randomized trials exist that provide more robust causal evidence [5].

Exposure measurement represents a recurring limitation: self-reported questionnaires remain widely used but are subject to recall bias and social desirability; objective measures (accelerometers) improve precision but are more expensive and less common in large cohorts [8].

Contextual variability—age, comorbidities, socio-economics, culture, and urban infrastructure—influences the observed effect and the transferability of estimates between countries. Finally, the type of activity (resistance vs. aerobic), the distribution of movement throughout the day, and time spent sitting interact with the observed effects: for example, evidence suggests that very high volumes of activity can attenuate, but not always eliminate, the negative effects of long periods of sedentary behavior [8].

Key takeaways

• Physical activity includes daily movement and structured exercise; both contribute to health.
• Transitioning from inactivity to moderate levels of activity yields the greatest benefits in terms of disease risk and mortality [4].
• For glycemic control in people with diabetes, structured interventions show documented improvements in clinical studies [5].
• Associations exist with reduced risk for certain cancers and for mental distress, but the strength of evidence varies by outcome [6][9].
• Recommendations must be tailored to the individual's profile and verified with a healthcare professional when relevant medical conditions are present [3].

Editorial conclusion

Scientific literature confirms that physical activity is a powerful factor associated with better health and a lower incidence of many chronic diseases. The greatest benefits, both individual and collective, are achieved through policies and environments that facilitate daily movement and with personalized clinical interventions when necessary. At the same time, a critical reading of the evidence must be maintained: much data is observational and requires prudent interpretation. For individual clinical decisions and therapeutic programs, consultation with qualified professionals remains indispensable.

SCIENTIFIC RESEARCH

1. Guthold R, Stevens GA, Riley LM, Bull FC. Worldwide trends in insufficient physical activity from 2001 to 2016: a pooled analysis of 358 population‑based surveys with 1·9 million participants. Lancet Glob Health. 2018;6(10):e1077‑e1086. https://doi.org/10.1016/S2214-109X(18)30357-7
2. Lee I‑M, Shiroma EJ, Lobelo F, et al. Effect of physical inactivity on major non‑communicable diseases worldwide: an analysis of burden of disease and life expectancy. Lancet. 2012;380(9838):219‑229. https://doi.org/10.1016/S0140-6736(12)61031-9
3. Piepoli MF, Hoes AW, Agewall S, et al. 2016 European Guidelines on cardiovascular disease prevention in clinical practice. Eur Heart J. 2016;37(29):2315‑2381. https://doi.org/10.1093/eurheartj/ehw106
4. Arem H, Moore SC, Patel A, et al. Leisure time physical activity and mortality: a detailed pooled analysis of the dose‑response relationship. JAMA Intern Med. 2015;175(6):959‑967. https://doi.org/10.1001/jamainternmed.2015.0533
5. Umpierre D, Ribeiro PA, Kramer CK, et al. Physical activity advice only or structured exercise training and association with HbA1c levels in type 2 diabetes: a systematic review and meta‑analysis. JAMA. 2011;305(17):1790‑1799. https://doi.org/10.1001/jama.2011.576
6. Moore SC, Lee I‑M, Weiderpass E, et al. Association of leisure‑time physical activity with risk of 26 types of cancer in 1.44 million adults. JAMA Intern Med. 2016;176(6):816‑825. https://doi.org/10.1001/jamainternmed.2016.1548
7. Cornelissen VA, Smart NA. Exercise training for blood pressure: a systematic review and meta‑analysis. J Am Heart Assoc. 2013;2(1):e004473. https://doi.org/10.1161/JAHA.112.004473
8. Ekelund U, Steene‑Johannessen J, Brown WJ, et al. Does physical activity attenuate, or even eliminate, the detrimental association of sitting time with mortality? A harmonised meta‑analysis of data from more than 1 million men and women. Lancet. 2016;388(10051):1302‑1310. https://doi.org/10.1016/S0140-6736(16)30370-1
9. Schuch FB, Vancampfort D, Firth J, et al. Physical activity and incident depression: a meta‑analysis of prospective cohort studies. Am J Psychiatry. 2018;175(7):631‑648. https://doi.org/10.1176/appi.ajp.2018.17111194