Foam Energy Return

Calculate foam energy return from the supplied measurements.

Description

Foam energy return compares recovered mechanical energy with input energy.

Foam energy return compares recovered mechanical energy with input energy. The shared helper returns the percentage without enforcing a physical energy balance.^[1]

Calculate foam energy return from the supplied measurements.

When to use Foam Energy Return

Use this tool to calculate foam energy return from the supplied measurements.

Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.

How to use Foam Energy Return and understand its results

Prepare the measured movement, timing, load or preassigned score requested. Keep protocols, units, paired measurements and caller-selected thresholds consistent.
Enter returnedEnergyJoules, inputEnergyJoules using the field table and calculation rules, then run the tool.
Read energyReturnPercent. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
returnedEnergyJoules	Returned energy	number	Required
inputEnergyJoules	Input energy	number	Required

Enter finite energies with nonzero input. Signed values and percentages outside 0–100 are accepted. Return percentage.

return%=100returnedJ/inputJ

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
energyReturnPercent	Energy return (%)	number

json

{
  "input": {
    "returnedEnergyJoules": 65,
    "inputEnergyJoules": 100
  },
  "output": {
    "energyReturnPercent": 65
  }
}

Limitations and assumptions

Use a positive input basis for interpretation. No hysteresis loop, test protocol, durability or running benefit is modeled.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Shoe Heel Drop: Compute heel-to-forefoot shoe drop and screen a supplied zero-drop tolerance. For a complementary task, use Leg Stiffness: Calculate leg stiffness from the supplied measurements.

References

Foam Energy Return — tool.io

Similar or alternative tools

Shoe Heel Drop
Compute heel-to-forefoot shoe drop and screen a supplied zero-drop tolerance.
Leg Stiffness
Calculate leg stiffness from the supplied measurements.