calculate_exposure: Calculate Training Load Exposure (ATL, CTL, ACWR)

In Athlytics: Advanced Sports Performance Analysis for 'Strava' Data

Calculate Training Load Exposure (ATL, CTL, ACWR)

Description

Calculates training load metrics like ATL, CTL, and ACWR from Strava data.

Usage

calculate_exposure(
  stoken,
  activity_type = c("Run", "Ride", "VirtualRide", "VirtualRun"),
  load_metric = "duration_mins",
  acute_period = 7,
  chronic_period = 42,
  user_ftp = NULL,
  user_max_hr = NULL,
  user_resting_hr = NULL,
  end_date = NULL
)

Arguments

stoken	A valid Strava token from 'rStrava::strava_oauth()'.
activity_type	Type(s) of activities to include (e.g., "Run", "Ride"). Default includes common run/ride types.
load_metric	Method for calculating daily load (e.g., "duration_mins", "distance_km", "tss", "hrss"). Default "duration_mins".
acute_period	Days for the acute load window (e.g., 7).
chronic_period	Days for the chronic load window (e.g., 42). Must be greater than 'acute_period'.
user_ftp	Required if 'load_metric = "tss"'. Your Functional Threshold Power.
user_max_hr	Required if 'load_metric = "hrss"'. Your maximum heart rate.
user_resting_hr	Required if 'load_metric = "hrss"'. Your resting heart rate.
end_date	Optional. Analysis end date (YYYY-MM-DD string or Date). Defaults to today. The analysis period covers the 'chronic_period' days ending on this date.

Details

Calculates daily load, ATL, CTL, and ACWR from Strava activities based on the chosen metric and periods.

Provides data for 'plot_exposure'. Fetches extra prior data for accurate initial CTL. Requires FTP/HR parameters for TSS/HRSS metrics.

Value

A data frame with columns: 'date', 'daily_load', 'atl' (Acute Load), 'ctl' (Chronic Load), and 'acwr' (Acute:Chronic Ratio) for the analysis period.

Examples

# Example using simulated data
data(Athlytics_sample_data)
print(head(athlytics_sample_exposure))

## Not run: 
# Example using real data (requires authentication)
# Replace YOUR_APP, YOUR_ID, YOUR_SECRET with your Strava application details
# stoken_example <- rStrava::strava_oauth(app_name = "YOUR_APP",
#                                client_id = "YOUR_ID",
#                                client_secret = "YOUR_SECRET",
#                                cache = TRUE)

# Calculate training load for Rides using TSS
# Ensure stoken_example is defined and valid before running this part
# if (exists("stoken_example") && inherits(stoken_example, "Token2.0")) {
#   ride_exposure_tss <- calculate_exposure(
#     stoken = stoken_example,
#     activity_type = "Ride",
#     load_metric = "tss",
#     user_ftp = 280,
#     acute_period = 7,
#     chronic_period = 28
#   )
#   print(head(ride_exposure_tss))
#
#   # Calculate training load for Runs using HRSS
#   run_exposure_hrss <- calculate_exposure(
#       stoken = stoken_example,
#       activity_type = "Run",
#       load_metric = "hrss",
#       user_max_hr = 190,
#       user_resting_hr = 50
#   )
#   print(tail(run_exposure_hrss))
# } else {
#   message("stoken_example not created. Skipping real data examples for calculate_exposure.")
# }

## End(Not run)

Athlytics documentation built on June 8, 2025, 1:11 p.m.