{
  "resourceType": "ActivityDefinition",
  "id": "hammer-curl",
  "url": "https://bodyiq.dev/fhir/ActivityDefinition/hammer-curl",
  "version": "1",
  "name": "HammerCurl",
  "title": "Hammer Curl",
  "status": "draft",
  "experimental": true,
  "description": "Stand holding a dumbbell in each hand at your sides with palms facing your thighs (neutral grip). Keeping the elbows pinned to your ribs and the thumbs pointing up throughout, bend the elbows to curl the weights toward the shoulders, then lower with control back to full elbow extension.",
  "useContext": [
    {
      "code": {
        "system": "http://terminology.hl7.org/CodeSystem/usage-context-type",
        "code": "user"
      },
      "valueCodeableConcept": {
        "text": "difficulty: beginner"
      }
    }
  ],
  "topic": [
    {
      "coding": [
        {
          "system": "https://bodyiq.dev/fhir/CodeSystem/exercise",
          "code": "hammer-curl",
          "display": "Hammer Curl"
        }
      ]
    }
  ],
  "bodySite": [
    {
      "coding": [
        {
          "system": "https://bodyiq.dev/fhir/CodeSystem/exercise",
          "code": "elbow",
          "display": "Elbow"
        },
        {
          "system": "http://snomed.info/sct",
          "code": "44034005",
          "display": "Structure of humeroulnar joint"
        }
      ],
      "text": "Elbow"
    }
  ],
  "kind": "ServiceRequest",
  "dosage": [
    {
      "text": "2-4 sets of 8-12 repetitions at a moderate load (roughly 65-80% 1RM or 2-3 reps in reserve), 2-3 sessions per week, consistent with general resistance-training guidelines for hypertrophy and strength; no hammer-curl-specific dosing trials exist."
    }
  ],
  "usage": "Evidence: limited. Surface EMG comparisons of curl grip positions indicate that a neutral (hammer) grip produces relatively higher brachioradialis activation and somewhat lower biceps brachii activation than a supinated grip, because the biceps loses mechanical advantage as a supinator-flexor when the forearm is held in mid-position. The brachialis, inserting on the ulna, flexes the elbow irrespective of forearm rotation and is strongly recruited in all curl variants. Wrist flexors and extensors co-contract isometrically to keep the wrist neutral, and finger flexors work isometrically for grip. Overall the direct EMG literature on hammer curls specifically is sparse; most inferences come from studies of elbow-flexion tasks at varying forearm rotations.",
  "note": [
    {
      "text": "Hold the dumbbells like hammers — thumbs up, palms facing each other the whole time."
    },
    {
      "text": "Imagine your elbows are pinned to your ribs with a strap; only your forearms move."
    },
    {
      "text": "Bring the top of the dumbbell toward your shoulder without letting the weight tip forward or back."
    },
    {
      "text": "Lower for a slow count of three until the arm is fully straight — no dropping the weight."
    }
  ],
  "extension": [
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Brachioradialis"
        },
        {
          "url": "role",
          "valueCode": "primary"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "72111005"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Brachialis"
        },
        {
          "url": "role",
          "valueCode": "primary"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "75915005"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Biceps Brachii"
        },
        {
          "url": "role",
          "valueCode": "secondary"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "16225001"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Anterior Deltoid"
        },
        {
          "url": "role",
          "valueCode": "stabilizer"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "35259002"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Flexor Digitorum Superficialis"
        },
        {
          "url": "role",
          "valueCode": "stabilizer"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "89895007"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Flexor Digitorum Profundus"
        },
        {
          "url": "role",
          "valueCode": "stabilizer"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "423541009"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Flexor Carpi Ulnaris"
        },
        {
          "url": "role",
          "valueCode": "stabilizer"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "14437004"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Extensor Carpi Radialis Longus"
        },
        {
          "url": "role",
          "valueCode": "stabilizer"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "39421004"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Upper Trapezius"
        },
        {
          "url": "role",
          "valueCode": "stabilizer"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "31764008"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Triceps Brachii"
        },
        {
          "url": "role",
          "valueCode": "lengthening"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "40284004"
          }
        }
      ]
    }
  ]
}