Deep tissue without the bruising
"No pain, no gain" is bad advice on a massage table.
Effective deep-tissue work is slow, not brutal. Pressure that arrives gradually lets the muscle yield; pressure that arrives suddenly makes it fight back, and fighting muscle is how people end up bruised and stiffer than before.
There is a useful line between good discomfort and real pain. A deep ache you can breathe through is the work happening. A sharp, hold-your-breath pain is a signal to ease off, and any good therapist wants you to say so.
You should leave a deep-tissue session feeling lighter, maybe a little tender — not battered. If a massage regularly leaves marks, the pressure was wrong, not heroic.