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Family of functions that serve a purpose of probing sprint or force-velocity profile. This is done by increasing individual sprint parameter for a percentage and calculating which parameter improvement yield biggest deduction in sprint tim

probe_FV "probes" F0 and V0 and calculates which one improves sprint time for a defined distance

probe_MSS_MAC "probes" MSS and MAC and calculates which one improves sprint time for a defined distance

Usage

probe_FV(
  distance,
  F0,
  V0,
  bodymass = 75,
  inertia = 0,
  resistance = 0,
  perc = 2.5,
  ...
)

probe_MSS_MAC(distance, MSS, MAC, perc = 2.5)

Arguments

distance

Numeric vector

F0, V0

Numeric vectors. FV profile parameters

bodymass

Body mass in kg

inertia

External inertia in kg (for example a weight vest, or a sled). Not included in the air resistance calculation

resistance

External horizontal resistance in Newtons (for example tether device or a sled friction resistance)

perc

Numeric vector. Probing percentage. Default is 2.5 percent

...

Arguments passed on to get_air_resistance

velocity

Instantaneous running velocity in meters per second (m/s)

bodyheight

In meters (m). Default is 1.75m

barometric_pressure

In Torrs. Default is 760Torrs

air_temperature

In Celzius (C). Default is 25C

wind_velocity

In meters per second (m/s). Use negative number as head wind, and positive number as back wind. Default is 0m/s (no wind)

MSS, MAC

Numeric vectors. Model parameters

Value

probe_FV returns a data frame with the following columns

F0

Original F0

V0

Original F0

bodymass

Bodymass

inertia

Inertia

resistance

Resistance

Pmax

Maximal power estimated using F0 * V0 / 4

Pmax_rel

Relative maximal power

slope

FV profile slope

distance

Distance

time

Time to cover distance

probe_perc

Probe percentage

F0_probe

Probing F0

F0_probe_time

Predicted time for distance when F0 is probed

F0_probe_time_gain

Difference in time to cover distance between time_optimal and time

V0_probe

Probing V0

V0_probe_time

Predicted time for distance when V0 is probed

V0_probe_time_gain

Difference in time to cover distance between time_optimal and time

profile_imb

Percent ratio between V0_probe_time_gain and F0_probe_time_gain

probe_MSS_MAC returns a data frame with the following columns

MSS

Original MSS

MAC

Original MAC

Pmax_rel

Relative maximal power estimated using MSS * MAC / 4

slope

Sprint profile slope

distance

Distance

time

Time to cover distance

probe_perc

Probe percentage

MSS_probe

Probing MSS

MSS_probe_time

Predicted time for distance when MSS is probed

MSS_probe_time_gain

Difference in time to cover distance between probe time and time

MAC_probe

Probing MAC

MAC_probe_time

Predicted time for distance when MAC is probed

MAC_probe_time_gain

Difference in time to cover distance between probing time and time

profile_imb

Percent ratio between MSS_probe_time_gain and MAC_probe_time_gain

Examples

MSS <- 10
MAC <- 8
bodymass <- 75

fv <- create_FVP(MSS, MAC, bodymass)

dist <- seq(5, 40, by = 5)

probe_MSS_MAC_profile <- probe_MSS_MAC(
  distance = dist,
  MSS,
  MAC
)[["profile_imb"]]

probe_FV_profile <- probe_FV(
  distance = dist,
  fv$F0,
  fv$V0,
  fv$bodymass
)[["profile_imb"]]

plot(x = dist, y = probe_MSS_MAC_profile, type = "l", ylab = "Profile imbalance")
lines(x = dist, y = probe_FV_profile, type = "l", col = "blue")
abline(h = 100, col = "gray", lty = 2)