I would recommend that you see your primary care doctor
about this issue, especially if the tightness and stiffness is getting in the way of your normal activities or if it is persistent or worsening.
There are several potential causes of the symptoms that your doctor will consider. In people who have physically demanding jobs or who exercise a great deal, morning stiffness is common, especially after a hard day or heavy work out. Typically, if this is what is going on, the symptoms will resolve with increased rest time and decreasing your physical activity level a bit.
There are, however, several other causes of stiffness. First, it will be important for your doctor to look for any swelling or pain in the joints (as opposed to the muscles), as joint involvement invokes a different series of potential rheumatologic causes, such as rheumatoid arthritis
Even if there is no evidence of joint involvement, it is likely worthwhile to have some basic blood work done, to look at your thyroid function and, potentially, to evaluate for any evidence of muscle inflammation or damage. Your doctor can help you determine what, exactly, to evaluate for based on the findings of their physical examination.