Read more Body Symmetries and Muscle Coordination Our muscle mass and strength declines as we age. Generally, side effects seem to relate to poor hygiene and training of the acupuncturist. The tip of the needle should not be made too sharp to prevent breakage, although blunt needles cause more pain. 50 Apart from the usual filiform needle, other needle types include three-edged needles and the Nine Ancient Needles. 49 Japanese acupuncturists use extremely thin needles that are used superficially, sometimes without penetrating the skin, and surrounded by a guide tube a 17th-century invention adopted in China and the West. Typically, the acupuncturist will use 6-12 needles during the treatment.