Physical activity as a key issue for promoting human health on a local and global scale: evidences and perspectives.

Physical inactivity represents the fourth leading risk factor with the highest epidemiological impact on population health worldwide, as estimated by the epidemiological measures used in global surveillance systems as the Global Burden of Disease Study. Scientific research has provided compelling evidence to establish and clarify the causal relationships and to devise effective intervention strategies, including the development of both national and international recommendations and the planning of whole-of-system and integrated actions. Over the last few years, new paradigms have been identified, such as the distinction between physical inactivity and sedentary behaviour, the different methods to integrate enough levels of physical activity in daily life, and the relevance of sleep in normal lifestyle activities. The experience in programs planning and in their assessments has led to the definition of a whole-of-system and global approach for the promotion of an active lifestyle, specifically the Global Action Plan on Physical Activity 2018 - 2030 by the World Health Organization, with the definition of overlapping areas with further objectives of public health as established by the 2030 Agenda for Sustainable Development. Thus, the action plan aims to ensure access to inclusive and equitable opportunities for people to be physically active in their daily life (with reference to more socially disadvantaged groups, such as women, people with disabilities, people of low socioeconomic status) and to improve planetary health.

Comparative effects of red blood cell transfusion and increasing blood flow on tissue oxygenation in oxygen supply-dependent conditions.

Red blood cell (RBC) transfusion is usually administered to improve oxygen delivery (DO(2)) in order to sustain tissue oxygen demand. However, this practice is not supported by firm clinical or experimental data. Using a randomized two-period crossover design, this study compared the efficacy of "fresh" RBC transfusion and increased blood flow to restore tissue oxygenation in oxygen supply-dependent conditions. In 12 ketamine-anesthetized mongrel dogs submitted to nonpulsatile normothermic cardiopulmonary bypass, DO(2) was reduced by a progressive decrease in pump flow. DO(2) dependency was defined as an O(2) uptake (V O(2)) decrease by more than 15% from baseline value. Then, intervention consisted of a 40% increase in DO(2) obtained either by transfusion of "fresh" dog's RBC (stored < 3 d) or by increase in pump flow. Animals received both interventions sequentially in a random order, while O(2) saturation was maintained constant. In O(2) supply-dependent conditions, rising pump flow from 1.6 +/- 0.4 to 2.7 +/- 0.7 L/ min increased DO(2) from 5.4 +/- 1.1 to 9.0 +/- 1.3 ml/kg/min (p < 0.01) and V O(2) from 3.5 +/- 0.4 to 4.1 +/- 0.5 ml/kg/min (p = 0.02). "Fresh" RBC transfusion, which increased the hemoglobin concentration from 6.4 +/- 0.9 to 11.1 +/- 1.3 g/dl, increased DO(2) from 5.4 +/- 1.2 to 9.0 +/- 1.4 ml/kg/min (p < 0.01) and V O(2) from 3.6 +/- 0.4 to 4.1 +/- 0.5 ml/kg/min (p = 0.02). There was no difference in V O(2) resulting from both interventions. In oxygen supply-dependent conditions, "fresh" RBC transfusion and increased blood flow are equally effective in restoring tissue oxygenation.