Skeletal muscles have a fundamental role in locomotion and whole body metabolism, with muscle mass and quality being linked to improved health and even lifespan. Optimising nutrition in combination with exercise is considered an established, effective ergogenic practice for athletic performance. Importantly, exercise and nutritional approaches also remain arguably the most effective countermeasure for muscle dysfunction associated with ageing and numerous clinical conditions e.g. cancer cachexia, COPD and organ failure, via engendering favourable adaptations such as increased muscle mass and oxidative capacity. Therefore, it is important to consider the effects of established and novel effectors of muscle mass, function and metabolism in relation to nutrition and exercise. To address this gap, in this review we detail existing evidence surrounding the efficacy of a non-exhaustive list of macronutrient, micronutrient and "nutraceutical" compounds alone and in combination with exercise in relation to skeletal muscle mass, (protein and fuel) metabolism and exercise performance (i.e. strength and endurance capacity). It is long established that macronutrients have specific roles and impacts upon protein metabolism and exercise performance i.e. protein positively influences muscle muscle mass and protein metabolism, whilst carbohydrate and fat intakes can influence fuel metabolism and exercise performance. Regarding novel nutraceuticals, we show the following ones in particular may have effects in relation to: 1) muscle mass/protein metabolism: leucine, hydroxyl b-methylbutyrate, creatine, vitamin-D, ursolic acid and phosphatidic acid, and 2) exercise performance: (i.e. strength or endurance capacity); hydroxyl -methylbutyrate, carnitine, creatine, nitrates and b-alanine.