The review aims to explore the potential benefit and risk of high-protein diets (HPD) regarding the comorbidity of sarcopoenia and CVD in the setting of cardiac rehabilitation (CR). CR is standard care for individuals who have experienced a cardiac event, but the current practice of predominantly aerobic exercise, a lower-fat diet and weight loss poorly addresses the issue of sarcopoenia. HPD, especially when combined with resistance exercise (RE), may be valuable adjuncts to current CR practice and benefit both muscle and cardiovascular health. Meta-analyses and randomised controlled trials of HPD and CVD risk show beneficial but variable effects regarding weight loss, the lipid profile, insulin resistance and lean body mass in those living with or high risk of CVD. Meta-analyses of prospective cohort studies on hard CVD endpoints favour lower- and plant-protein diets over higher animal protein, but the evidence is inconsistent. HPD augment the strength and muscle gaining benefits of RE in older populations, but there are no published data in those living with CVD providing promising opportunities for CR research. HPD raise concern regarding renal and bone health, the microbiome, branched chain amino acids and environmental sustainability and findings suggest that plant-based HPD may confer ecological and overall health advantages compared to animal-based HPD. However, incorporating RE with HPD might alleviate certain health risks. In conclusion, a largely plant-based HPD is deemed favourable for CR when combined with RE, but further research regarding efficacy and safety in CR populations is needed.

A progressive decrement in muscle mass and muscle function, sarcopoenia, accompanies ageing. The loss of skeletal muscle mass and function is the main feature of sarcopoenia. Preventing the loss of muscle mass is relevant since sarcopoenia can have a significant impact on mobility and the quality of life of older people. Dietary protein and physical activity have an essential role in slowing muscle mass loss and helping to maintain muscle function. However, the current recommendations for daily protein ingestion for older persons appear to be too low and are in need of adjustment. In this review, we discuss the skeletal muscle response to protein ingestion, and review the data examining current dietary protein recommendations in the older subjects. Furthermore, we review the concept of protein quality and the important role that nutrient-dense protein (NDP) sources play in meeting overall nutrient requirements and improving dietary quality. Overall, the current evidence endorses an increase in the daily ingestion of protein with emphasis on the ingestion of NDP choices by older adults.