DOMS (delayed onset muscle soreness) it is completely normal. DOMS usually begin within 6-8 hours after a new activity or a change in activity and can last up to 24-48 hours after the exercise.
Why do they get sore?
Our muscles get sore when we overload them by doing something that is different to normal. That might be doing more exercise than normal or lifting more weight, more reps, more sets. In everyday life it might be doing more gardening, getting back on the golf course, moving furniture or boxes etc you get the idea.
What helps the sore muscle?
To boost recovery, incorporate foam rolling, stretching, gentle walking and swimming. The main thing that works is time and following a regular fitness programme.
Do I have to have sore muscles after a workout?
While soreness is usually the result of a hard workout, it’s not necessary to be sore after every workout to experience results. When starting a new programme or routine it is common to be sore for the first few sessions. After a few weeks of the same workouts our body will adapt, and you will no longer be sore.