Well, it doesn't have to be that abstract. Muscles in the peripheral limbs, particularly the lower leg but also the forearm, are important in returning venous b

Well, it doesn't have to be that abstract. Muscles in the peripheral limbs, particularly the lower leg but also the forearm, are important in returning venous blood to the heart. In fact, the gastrocnemius (calf muscle) has been referred to as the "second heart": https://veinatlanta.com/your-second-heart/ https://veinatlanta.com/your-second-heart/