Pinch the skin: Gently pinch a small fold of skin and insert the needle at a 45-degree angle
Lancet 395 , 18451854 (2020)
This provides a reasonable explanation for the limited correlation between hotspots and superficial sites, as exemplified by S1 and S4

Ingredients: Aqua, Niacinamide, Glycerin, Glutathione, Cynocobalamin, Dipropylene, Glyco/Hydrogenated Lecithin, Prunus Speciosa Flower Extract, Ceramides NP, Sophora Angustifolia Root Extract, Glycyrrhiza Inflata Root Extract, Scutellaria Baicalensis Root Extract, Artemisia Princeps Leaf Extract, Camellia Japonica Seed Extract, Ceramide NS/Ceramides NG, Ceramides AS, Ceramide EOP, Ceramide AP, Cyclopentasiloxane, Triethyhexanoin, PEG/PPG-17/6, Copolymer, Butylene Glycol, Propanediol Isononyl Isononanoate, Caprylic/Capric Triglyceride, BIS-PEG-15 Methyl Ether Dimethicone, Cyclohexasiloxane, 1,2-Hexanediol Hydroxyacetophenone, PEG-40 Hydrogenated Castor Oil, Glyceryl Stearate, PEG-100 Stearate Polyacrylic Acid, Dimethicone Crosspolymer, Phenoxyethanol, Vaccinium Myrtillus Fruit Extract, Methylparaben, Maltodextrin, Sodium Hydroxide, Propylparaben, Sodium Hyaluronate, Ethylhexylglycerin, Aroma, Citric Acid, Sodium Citrate, AKA226,CI 47000

Intense exercise often leads to muscle microtears, which cause inflammation and soreness