Where It Is Safe to Hit: The Impact Play Safety Map (Body Zones, Organs, Nerves, and Bone)
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I run The BDSM Store and test the gear I recommend. Everything here is first-hand experience, not medical advice.
The safe places to hit in impact play are the places where thick muscle and fat sit over nothing important: the buttocks above all, the upper and outer thighs, the upper back across the shoulder blades on either side of the spine, and the calves. The unsafe places are where bone, organs, or nerves are close to the surface: the lower back and sides over the kidneys, the spine, the tailbone, the neck and head, the backs of the knees and the insides of the elbows, the hands and feet, the belly, and the front of the body generally. Between them are zones that take light sensation and specific implements and nothing heavy: the breasts and chest, the inner thighs, the palms and soles, the belly for taps, and the genitals under their own rules. Every implement guide on this site refers back to this page, because the single most important thing a top learns is not how to swing but where.
I have seen the injuries that come from not knowing this map: a kidney bruise from a flogger thrown low, a tailbone that hurt for months from a paddle landed high, a hand that went numb from a crop across the inside of the elbow, a split cheek from a face slap with a ring on. None of them happened to people who were being careless in general; they happened to people who did not know that an inch made the difference. This guide gives the map zone by zone with the anatomy behind it, a table of what each implement is allowed where, the special case of face slapping, the signs of an injury in progress and after, when to see a doctor and what to say, and the health conditions that move the lines.
This is the safety chapter of impact play 101. The nerve and circulation rules for restraint are in bondage safety; the genital rules are in CBT; the recovery is in aftercare.
The principle: muscle and fat over nothing important
Impact is absorbed by muscle and fat. Where there is a thick layer of both, force spreads and dissipates into tissue that bruises and heals; where bone is close to the surface, the force goes into the bone (pain, fracture risk, long-lasting bruising of the periosteum); where an organ is close, the force goes into the organ (the kidneys are the concern, and they sit just under the lower ribs at the back and sides, lower and more exposed than people think); where a nerve runs close to the surface (the backs of the knees, the insides of the elbows, the outside of the knee, the inside of the upper arm), the force goes into the nerve (numbness, tingling, weakness that can last weeks). So the map is simple in principle: the big padded muscles are the targets, and everything else is off, with the lighter implements allowed a little further because they carry less force. The buttocks are the best target on the body because they are the largest muscle covered by the thickest fat with nothing beneath but more muscle and, deep down, the pelvis.
Green zones: hit here
| Zone | Why it is safe | Notes |
|---|---|---|
| Buttocks (the fleshy lower and middle of each cheek) | Gluteus maximus, the body's largest muscle, under the thickest fat layer; no organs, bone well buried | The target for everything; the "sit spot" at the crease is the sweet spot; stay off the tailbone at the top-centre and the hip bones at the outer-upper corner |
| Upper and outer thighs (the back and outside of the thigh from the crease to a hand above the knee) | Hamstrings and the outer thigh muscles; thick, no organs | Stingier than the buttocks, less padding; heavy implements lighter here; stop a hand's width above the knee |
| Upper back (across the shoulder blades and the big muscles either side of the spine, from the shoulders to the bottom of the ribcage) | Trapezius, rhomboids, latissimus; the shoulder blades are flat bone under muscle and take flat impact well | Floggers and hands; nothing with an edge (canes, crops, paddles on edge); the spine down the middle is red; stop at the bottom of the ribs, because below that is the kidney zone |
| Calves | Thick muscle | Light to moderate implements; sensitive; stay off the back of the knee above and the Achilles below |
Yellow zones: light and specific only
| Zone | What is allowed | Why the limit |
|---|---|---|
| Breasts | Hands, light floggers, crop taps and flicks, by specific agreement | Glandular tissue bruises and can develop lumps; nothing heavy, nothing with an edge; no impact over implants without a conversation |
| Chest (for people without breast tissue) | Hands, floggers, moderate force on the pectorals | Ribs and the sternum are close; the collarbone is red; nothing heavy |
| Inner thighs | Hands, crop taps and light flicks, light floggers | Thin skin, the femoral artery and nerve run on the inside of the thigh; very sensitive, which is the appeal; light only |
| Palms and soles | Crop and cane taps and light strokes, in traditional discipline | Bones, tendons, and nerves close to the surface; light strokes only; the soles are a traditional target (bastinado) that injures with force |
| Belly | Hands and crop taps only, light | Organs with no protection; nothing with force, ever |
| Genitals | Within the rules of CBT for the penis and testicles; hands and the lightest crop taps for the vulva | Specific anatomy and specific risks; a separate guide |
| Upper arms (outer) | Hands, light floggers | The radial nerve runs round the back of the upper arm; the inside of the arm is red |
| Shoulders (the tops) | Hands, light floggers | Bone close; the neck is next door |
Red zones: never
| Zone | Why |
|---|---|
| Lower back and sides (from the bottom of the ribs to the top of the pelvis, all the way round to the flanks) | The kidneys sit here, just under the last ribs at the back, with no bone in front of them below the ribs. A blow can bruise or rupture a kidney; blood in the urine after a scene is a kidney injury. This is the most common serious impact injury and it comes from floggers thrown low and paddles landed high. |
| Spine (the line of bone down the centre of the back, from the neck to the tailbone) | Vertebrae with no padding; the spinal cord inside. Floggers land either side, never down the middle; canes and paddles never on the back at all. |
| Tailbone (coccyx) and the top of the cleft | Bone just under the skin; a bruised coccyx hurts for months and a fractured one longer. Paddles and canes landed too high on the buttocks hit it. |
| Hip bones (the iliac crest, the ridge at the side of the pelvis) | Bone under thin skin; where canes and flogger tails wrap to; bruises for weeks. |
| Neck, throat, and head | Airway, arteries, spine, brain. Nothing, ever, with any implement. See choking for why the neck is the line in all of kink. |
| Backs of the knees | The peroneal and tibial nerves and the popliteal artery, with no padding; a blow causes numbness and foot drop. |
| Insides of the elbows and the inside of the upper arm | The ulnar and median nerves and the brachial artery; numbness and weakness in the hand. |
| Outside of the knee, just below the joint | The peroneal nerve passes over bone here; the single most exposed nerve on the body. |
| Joints generally (knees, elbows, ankles, wrists, shoulders) | Bone, ligament, and nerve; nothing to absorb force. |
| Hands and feet (tops and sides) | Small bones and tendons under thin skin; fractures. |
| Collarbone and sternum | Bone under skin; fractures. |
| Ears | A slap over the ear can rupture the eardrum. |
| Front of the body generally (ribs, belly, groin) with anything but hands and taps | Organs and bone; the front has no large padded muscle except the chest. |
What each implement is allowed where
| Implement | Buttocks | Upper/outer thighs | Upper back | Calves | Breasts/chest | Inner thighs | Palms/soles | Genitals |
|---|---|---|---|---|---|---|---|---|
| Hand | Yes | Yes | Yes | Yes | Light | Light | Light | CBT rules |
| Soft flogger | Yes | Yes | Yes | Yes | Light | Light | No | Very light, by agreement |
| Heavy flogger | Yes | Moderate | Yes | No | No | No | No | No |
| Paddle (soft) | Yes | Yes | No | Light | No | No | No | No |
| Paddle (wood/acrylic) | Yes | Light | No | No | No | No | No | No |
| Crop | Yes | Yes | Taps/flicks | Taps/flicks | Taps/flicks | Taps/flicks | Taps/flicks | Taps; CBT rules |
| Cane | Yes | Light, upper only | No | No | No | No | Light, traditional | No |
| Tawse/strap/belt | Yes | Light | No | No | No | No | Light (tawse tradition) | No |
| Single-tail whip | Trained | Trained | Trained | No | No | No | No | No |
| Fists/knees | Yes (trained) | Yes (trained) | Yes (trained) | No | Chest only, trained | No | No | No |
Face slapping
Face slapping is its own practice with its own rules, because the face is a red zone that a great many people nonetheless want slapped. The risks are the ear (a cupped hand over the ear can rupture the eardrum), the eye, the jaw and teeth (a blow to the jaw can dislocate it or crack a tooth), the nose, and the neck (a slap that lands low or that snaps the head sideways). Done as the community does it: open hand, fingers together, no rings; the slap lands on the cheek, the fleshy part below the cheekbone and in front of the ear, with the fingers, not the palm, and never over the ear; the top's other hand holds the far side of the bottom's face or head to stop the head snapping; force builds from a touch; the bottom's mouth is closed (teeth together, to protect the jaw and tongue); never on a bottom with a jaw, ear, eye, or neck condition; and never more than a light to moderate slap, ever, because the face has no padding. The appeal is the intimacy and the humiliation, not the force. It belongs with degradation as much as with impact.
The wrap: how green becomes red
The tips of a flogger, the end of a cane, the tails of a tawse, and the lash of a whip carry the most speed, and when they travel past the edge of the target they curl round the body and land on whatever is there: the hip bone, the flank over the kidney, the side of the thigh over the nerve, the front of the body. This is the mechanism by which most impact injuries happen on tops who know the map perfectly well; they aimed at the buttock and the tip went round to the hip. The prevention, repeated in every implement guide: the right distance (the tip stops on the far edge of the target), shorter implements, throws that stop rather than follow through across the body, and a bottom who is still. A tip that wraps is a stroke that is checked after.
Signs of injury during and after
- During, on the skin: white patches (blood pushed out; rest that spot), deep purple appearing fast (a bruise forming; stop there), broken skin, swelling.
- During, from the bottom: sharp, stabbing, or electric pain rather than the dull burn of impact (nerve or bone), numbness or tingling in a limb (nerve), nausea or faintness (shock, or a kidney or testicle blow), a change in breathing, a sudden silence.
- After: blood in the urine (kidney injury; see a doctor the same day), pain in the lower back that is deep rather than surface, numbness or weakness that lasts more than a few hours, a bruise that is hard, hot, or growing, pain over a bone that gets worse rather than better, a bruise over the tailbone with pain on sitting that persists, any injury to the ear, eye, or jaw.
When to see a doctor
Blood in the urine, deep lower-back pain, or flank pain after impact: the same day; say what happened ("blunt impact to the lower back during consensual play"), because it changes what they look for. Numbness, tingling, or weakness in a limb that persists past a few hours: within a day or two; nerve injuries recover better with early assessment. Pain over a bone that worsens, a joint that will not bear weight, a suspected fracture: the same day. A bruise that is hard, hot, swelling, or growing a day later: a doctor, as it may be a haematoma that needs attention. Broken skin that reddens, weeps, or feels hot in the following days: a doctor, for infection. Anything to the ear, eye, or jaw: the same day. Emergency departments and doctors have seen consensual impact injuries before and will treat you better if you tell them what happened than if they have to guess; the kink-aware ones exist and the community knows who they are.
Health conditions that change the map
- Blood thinners and clotting disorders: bruising is deeper and longer; thud implements are limited; a conversation with a doctor before heavy play.
- Diabetes: slower healing and reduced sensation, especially in the legs and feet; the bottom may not feel damage; lighter play and careful checks.
- Nerve conditions, neuropathy, past nerve injuries: the nerve zones expand; avoid anything near the affected area.
- Kidney conditions: nothing anywhere near the lower back, and a lower threshold for stopping.
- Breast implants, surgical scars, hernias, recent surgery: no impact over any of them.
- Bone density conditions (osteoporosis): bone is a risk everywhere; heavy thud is out; hands and soft floggers only.
- Pregnancy: no impact on the belly, lower back, or breasts, and a conversation about everything else.
- Skin conditions, eczema, psoriasis: impact over affected skin breaks it; avoid.
- Heart conditions and blood pressure: the adrenaline of impact play is a cardiovascular event; discuss with a doctor; keep scenes moderate.
- Medications that thin skin or blood (some steroids, some painkillers): same as blood thinners.
The bottom discloses; the top adjusts. A bottom who hides a condition to get a harder scene has removed the top's ability to keep them safe, and the top should ask directly before any heavy play.
Frequently asked questions
Where is it safe to hit during impact play?
The buttocks (the best target: the largest muscle under the thickest fat), the upper and outer thighs, the upper back across the shoulder blades on either side of the spine, and the calves. These are the places where thick muscle and fat sit over nothing important.
Where should you never hit?
The lower back and sides (kidneys), the spine, the tailbone, the hip bones, the neck, throat, and head, the backs of the knees, the insides of the elbows and upper arms, the outside of the knee, joints, hands, feet, collarbone, sternum, ears, and the front of the body with anything but hands and taps.
Why is the lower back dangerous?
The kidneys sit just under the last ribs at the back and sides with no bone in front of them below the ribs, so a blow there can bruise or rupture a kidney. It is the most common serious impact injury, usually from floggers thrown low or paddles landed high. Blood in the urine after a scene means a doctor the same day.
Can you hit the breasts or chest?
Lightly, by specific agreement: hands, light floggers, and crop taps on the breasts, since glandular tissue bruises and can form lumps; hands and floggers at moderate force on the chest of someone without breast tissue, since ribs and sternum are close. Nothing heavy and nothing with an edge on either.
Is face slapping safe?
With rules: open hand, no rings, the fingers landing on the fleshy cheek below the cheekbone and never over the ear, the other hand steadying the head, the bottom's teeth together, force built from a touch and never more than light to moderate, and never with a jaw, ear, eye, or neck condition. The risks are the eardrum, eye, jaw, and neck.
What is the wrap in impact play?
The tips of a flogger, cane, tawse, or whip travelling past the edge of the target and curling round to land on the hip bone, flank, or front of the body. It causes most injuries on tops who know the map; prevent it with the right distance, shorter implements, throws that stop rather than follow through, and a still bottom.
What are the signs of an impact injury?
During: white patches or fast deep purple on the skin, broken skin, sharp stabbing or electric pain, numbness or tingling, nausea or faintness. After: blood in the urine, deep lower-back pain, numbness or weakness lasting hours, a hard, hot, or growing bruise, worsening pain over a bone, persistent tailbone pain, or any ear, eye, or jaw injury.
What health conditions affect impact play?
Blood thinners and clotting disorders, diabetes, nerve conditions, kidney conditions, implants and surgical scars, bone density conditions, pregnancy, skin conditions, heart and blood pressure conditions, and medications that thin skin or blood. The bottom discloses, the top asks directly and adjusts.