MMPs are enzymes involved in SARS-CoV-2 pathogenesis. Notably, the proteolytic activation of MMPs can occur through angiotensin II, immune cells, cytokines, and pro-oxidant agents. However, comprehensive information regarding the impact of MMPs in the different physiological systems with disease progression is not fully understood. In the current study, we review the recent biological advances in understanding the function of MMPs and examine time-course changes in MMPs during COVID-19. In addition, we explore the interplay between pre-existing comorbidities, disease severity, and MMPs. The reviewed studies showed increases in different MMP classes in the cerebrospinal fluid, lung, myocardium, peripheral blood cells, serum, and plasma in patients with COVID-19 compared to non-infected individuals. Individuals with arthritis, obesity, diabetes, hypertension, autoimmune diseases, and cancer had higher MMP levels when infected. Furthermore, this up-regulation may be associated with disease severity and the hospitalization period. Clarifying the molecular pathways and specific mechanisms that mediate MMP activity is important in developing optimized interventions to improve health and clinical outcomes during COVID-19. Furthermore, better knowledge of MMPs will likely provide possible pharmacological and non-pharmacological interventions. This relevant topic might add new concepts and implications for public health in the near future.

Aging is a natural process of organism deterioration, which possibly impairs multiple physiological functions. These harmful effects are linked to an accumulation of somatic mutations, oxidative stress, low-grade inflammation, protein damage, and mitochondrial dysfunction. It is known that these factors are capable of inducing telomere shortening, as well as intestinal dysbiosis. Otherwise, among the biological mechanisms triggered by physical exercise, the attenuation of pro-inflammatory mediators accompanied by redox state improvement can be the main mediators for microbiota homeostasis and telomere wear prevention. Thus, this review highlights how oxidative stress, inflammation, telomere attrition, and gut microbiota (GM) dysbiosis are interconnected. Above all, we provide a logical foundation for unraveling the role of physical exercise in this process. Based on the studies summarized in this article, exercise training can increase the biodiversity of beneficial microbial species, decrease low-grade inflammation and improve oxidative metabolism, these factors together possibly reduce telomeric shortening.

Background/Objectives: Programs combining resistance training with a concurrent cognitive demand are often presented as superior to resistance training alone, although the contribution of the cognitive component has never been quantified. This review quantified the effect of dual-task strength training (DTST) on dual-task performance, lower-limb strength, functional mobility, cognition and balance in older adults, relative to the same resistance program performed without the cognitive task. Methods: Three databases and Google Scholar were searched to March 2026 following PRISMA 2020, with eligibility requiring the cognitive task to be executed simultaneously with resistance exercise. Risk of bias was assessed with RoB 2 and ROBINS-I and certainty with GRADE, and random-effects models were fitted by restricted maximum likelihood. Results: Fourteen studies were included, and seven randomized trials with an active comparator entered the meta-analyses. Dual-task performance favored DTST (g = 0.53, 95% CI 0.25 to 0.81; 203 participants; I² = 0%; very low certainty), as did cognition (g = 0.91, 95% CI 0.34 to 1.49; 143 participants; I² = 7%; very low certainty), whereas lower-limb strength did not differ (g = 0.20, 95% CI −0.14 to 0.54; 135 participants; low certainty). The single-task Timed Up and Go favored DTST by 0.48 s (95% CI 0.09 to 0.88; 179 participants; low certainty), with a point estimate below the change regarded as clinically meaningful. Balance findings diverged across non-interchangeable instruments (I² = 87%), and only two studies monitored falls prospectively. Conclusions: DTST may make little or no difference to lower-limb strength and may slightly improve single-task mobility, whereas its effects on performance under cognitive constraint and on cognition are very uncertain despite favorable point estimates. Part of the dual-task gain may reflect practice on the task used at testing, and the evidence, of low to very low certainty, does not support DTST as a replacement for conventional resistance training.