Conventional and functional hamstring-to-quadriceps ratios

Computes the conventional concentric H:Q ratio and a functional ratio that compares eccentric antagonist torque with concentric agonist torque. Optional EMG traces are processed with processEMG() and summarised as the hamstring-to-quadriceps mean-envelope ratio.

Usage

hamstringQuadRatio(
  quad_con,
  ham_con,
  ham_ecc = NULL,
  quad_ecc = NULL,
  movement = c("extension", "flexion"),
  emg_ham = NULL,
  emg_quad = NULL,
  emg_sampling_rate = NULL
)

Arguments

quad_con: Concentric quadriceps peak torque or torque trace.
ham_con: Concentric hamstring peak torque or torque trace.
ham_ecc: Optional eccentric hamstring peak torque or torque trace.
quad_ecc: Optional eccentric quadriceps peak torque or torque trace.
movement: Movement direction, "extension" or "flexion".
emg_ham, emg_quad: Optional hamstring and quadriceps EMG traces. Supply both or neither.
emg_sampling_rate: EMG sampling rate in Hz, required with EMG traces.

Value

An hq_ratio object containing conventional and functional ratios, peak torques, movement direction, and optional EMG ratio.

References

Coombs R, Garbutt G (2002). Developments in the use of the hamstring/ quadriceps ratio for the assessment of muscle balance. Journal of Sports Science and Medicine, 1:56-62.

Aagaard P, Simonsen EB, Magnusson SP, Larsson B, Dyhre-Poulsen P (1998). A new concept for isokinetic hamstring:quadriceps muscle strength ratio. American Journal of Sports Medicine, 26:231-237. doi:10.1177/03635465980260021201

Examples

hamstringQuadRatio(quad_con = 200, ham_con = 120, ham_ecc = 150)
#> <hq_ratio> conventional H:Q 0.600
#>   functional (extension): 0.750