In recent years, scientists have discovered many mechanisms related to muscle mass gain. After intensive training, including a new training method or returning to exercise after 24-48 h, you felt – DOMS (delayed onset muscle soreness) or delayed muscle soreness. This is not a phenomenon directly related to lactic acid, because within an hour after the effort in the tissues there is no majority (if not all) of lactic acid (this depends on age, training, adaptation of muscle cells to a given type of effort).
One can only see an indirect relationship on the basis of the more intense the work (faster pace of running or swimming, shorter rest periods between sets, higher heart rate), the greater amount of lactic acid is produced.
After some time of conducting regular training, the muscles have adapted to the effort so much that you do not feel increased pain (there are less ailments, short-term). To get the original effect, you need to spend a lot of time pumping the biceps or stretching the chest with many different exercises. Are you wondering whether despite the smaller pain the muscles will increase in size? Fortunately, it has been found that for long-term muscle growth, soreness does not have to be intense and long-lasting. Muscle injuries arise in the chemical and mechanical way. Mechanical injuries originate from intense muscle work, especially in the fiber stretching phase (eccentric). It does not necessarily mean a large number of exercises and series, more important is the work time under load – ie, for example, lowering slowly, and the phase of lifting the weight a bit faster. Classic bending shoulders with a barbell standing has two phases – lifting the weight and lowering it. When lifting, the fibers shorten. In the eccentric phase, the two-headed muscle is stretched. In the resting phase, the contractile protein myosin and myosin do not form connections (bridges). Sometimes, when the weight is too big, the actin and myosin fibers are broken, which unfortunately damages the surrounding structures (deeper micro-injuries). If the muscle was extended further, with too much force – it would break. Similar damage can occur in the endurance effort when the mechanical load exceeds the fiber capacity
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