Wprime

W': work capacity above critical power/speed.

W': work capacity above critical power/speed.

Usage

Wprime(object, session = NULL, quantity = c("expended", "balance"), w0,
  cp, version = c("2015", "2012"), meanRecoveryPower = FALSE,
  parallel = FALSE, ...)

Details

#' Skiba et al. (2015) and Skiba et al. (2012) both describe an exponential decay of \(W'\) expended over an interval \([t_{i-1}, t_i)\) if the power output during this interval is below critical power:

$$W_exp (t_i) = W_exp(t_{i-1}) * exp(nu * (t_i - t_{i-1}))$$

However, the factor nu differs: Skiba et al. (2012) describe it as \(1/\tau\) with \(\tau\) estimated as

$$tau = 546 * exp(-0.01 * (CP - P_i)) + 316$$

Skiba et al. (2015) use \((P_i - CP) / W'_0\). Skiba et al. (2012) and Skiba et al. (2015) employ a constant recovery power (calculated as the mean over all power outputs below critical power). This rationale can be applied by setting the argument meanRecoveryPower to TRUE. Note that this uses information from all observations with a power output below critical power, not just those prior to the current time point.

References

Monod H, Scherrer J (1965). 'The Work Capacity of a Synergic Muscular Group.' Ergonomics, 8(3), 329--338.

Skiba PF, Chidnok W, Vanhatalo A, Jones AM (2012). 'Modeling the Expenditure and Reconstitution of Work Capacity above Critical Power.' Medicine & Science in Sports & Exercise, 44(8), 1526--1532.

Skiba PF, Fulford J, Clarke DC, Vanhatalo A, Jones AM (2015). 'Intramuscular Determinants of the Abilility to Recover Work Capacity above Critical Power.' European Journal of Applied Physiology, 115(4), 703--713.

Aliases

• Wprime
• trackeRWprime
• Based
• on
• the
• critical
• power
• model
• for
• cycling
• (Monod
• and
• Scherrer,
• 1965),
• W'
• (read
• W
• prime)
• describes
• finite
• work
• capacity
• above
• (Skiba
• et
• al.,
• 2012).
• While
• is
• depleted
• during
• exercise
• power,
• it
• replenished
• below
• power.
• Thus,
• of
• interest
• how
• much
• this
• has
• been
• not
• yet
• replinished
• again,
• named
• expended,
• or
• still
• available,
• balance.
• This
• principal
• applied
• to
• runners
• by
• subsituting
• with
• speed
• speed,
• respectively

Examples

# NOT RUN {
data('runs', package = 'trackeR')
wexp <- Wprime(runs, session = c(11,13), cp = 4, version = '2012')
plot(wexp)
# }