{
  "resourceType": "ActivityDefinition",
  "id": "depth-jump",
  "url": "https://bodyiq.dev/fhir/ActivityDefinition/depth-jump",
  "version": "1",
  "name": "DepthJump",
  "title": "Depth Jump (Drop Jump)",
  "status": "draft",
  "experimental": true,
  "description": "Step off a box, land, and immediately jump vertically. Peak impact forces 4.93-5.39 BW. Optimal drop height is 75-100% of squat jump height for bounce drop jumps. Training at optimal height produces 10-20% vertical jump improvement and 20-34% reactive strength index gains. Requires squat strength 1.5x BW.",
  "useContext": [
    {
      "code": {
        "system": "http://terminology.hl7.org/CodeSystem/usage-context-type",
        "code": "user"
      },
      "valueCodeableConcept": {
        "text": "difficulty: advanced"
      }
    }
  ],
  "topic": [
    {
      "coding": [
        {
          "system": "https://bodyiq.dev/fhir/CodeSystem/exercise",
          "code": "depth-jump",
          "display": "Depth Jump (Drop Jump)"
        }
      ]
    }
  ],
  "bodySite": [
    {
      "coding": [
        {
          "system": "https://bodyiq.dev/fhir/CodeSystem/exercise",
          "code": "hip",
          "display": "Hip"
        },
        {
          "system": "http://snomed.info/sct",
          "code": "24136001",
          "display": "Structure of hip joint"
        }
      ],
      "text": "Hip"
    },
    {
      "coding": [
        {
          "system": "https://bodyiq.dev/fhir/CodeSystem/exercise",
          "code": "knee",
          "display": "Knee"
        },
        {
          "system": "http://snomed.info/sct",
          "code": "129159008",
          "display": "Structure of femorotibial joint"
        }
      ],
      "text": "Knee"
    },
    {
      "coding": [
        {
          "system": "https://bodyiq.dev/fhir/CodeSystem/exercise",
          "code": "ankle",
          "display": "Ankle"
        },
        {
          "system": "http://snomed.info/sct",
          "code": "70258002",
          "display": "Structure of ankle joint"
        }
      ],
      "text": "Ankle"
    }
  ],
  "kind": "ServiceRequest",
  "dosage": [
    {
      "text": "1-2 sessions/week, 3×5 reps, 8 weeks. Drop height 75-100% of squat jump height [Yue 2025, Sotiropoulos 2023]"
    }
  ],
  "usage": "Evidence: moderate. GRF 4.93-5.39 BW. VL-BF, VM-BF, and RF-BF coactivation increases with height (ES 0.45-0.90) [Di Giminiani 2020]",
  "note": [
    {
      "text": "Stiff, springy contact — ground time stays minimal",
      "authorString": "focus:internal"
    },
    {
      "text": "Land and push the floor away as fast as possible",
      "authorString": "focus:external"
    },
    {
      "text": "Rebound straight up toward the ceiling",
      "authorString": "focus:external"
    },
    {
      "text": "Feet bounce off a hot stove — touch and launch",
      "authorString": "focus:imagery"
    }
  ],
  "relatedArtifact": [
    {
      "type": "citation",
      "label": "kisner-therapeutic-2017",
      "citation": "Kisner C, Colby LA, Borstad J. (2017). Therapeutic Exercise: Foundations and Techniques"
    },
    {
      "type": "citation",
      "label": "acsm-guidelines-2021",
      "citation": "American College of Sports Medicine. (2021). ACSM's Guidelines for Exercise Testing and Prescription",
      "document": {
        "url": "https://doi.org/10.4135/9781412994149.n165"
      }
    },
    {
      "type": "predecessor",
      "label": "Regress reactive/eccentric depth-jump landing to a concentric-only box jump when landing forces cannot be absorbed.",
      "display": "Box Jump (Bilateral)",
      "resource": "ActivityDefinition/box-jump"
    }
  ],
  "extension": [
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Gastrocnemius"
        },
        {
          "url": "role",
          "valueCode": "secondary"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "35616000"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Quadriceps Femoris"
        },
        {
          "url": "role",
          "valueCode": "primary"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "21989003"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Gluteus Maximus"
        },
        {
          "url": "role",
          "valueCode": "primary"
        },
        {
          "url": "coding",
          "valueCoding": {
            "system": "http://snomed.info/sct",
            "code": "206007"
          }
        }
      ]
    },
    {
      "url": "https://bodyiq.dev/fhir/StructureDefinition/muscle-involvement",
      "extension": [
        {
          "url": "muscle",
          "valueString": "Hamstrings (Group)"
        },
        {
          "url": "role",
          "valueCode": "stabilizer"
        }
      ]
    }
  ]
}