Generates a marathon training plan

marathon.py

import csv
from datetime import datetime, timedelta

START_DATE = datetime.today()
WEEKS = 15
INITIAL_DISTANCE = 35
MAX_INCREASE_RATE = 0.10
PARK_RUN_DISTANCE = 8
INCREASE_RATE = 0.05

headers = [
    "date",
    "monday",
    "tuesday",
    "wednesday",
    "thursday",
    "friday",
    "saturday",
    "sunday",
]

file_path = "training-plan.csv"

with open(file_path, mode="w", newline="") as file:
    writer = csv.writer(file)
    writer.writerow(headers)

    weekly_distance = INITIAL_DISTANCE
    distance_before_recovery = 0

    for week in range(WEEKS):
        if (week + 1) % 4 == 0:
            distance_before_recovery = weekly_distance
            weekly_distance *= 0.50

        elif distance_before_recovery > 0:
            weekly_distance = distance_before_recovery
            distance_before_recovery = 0

        interval_distance = weekly_distance * 0.20
        tempo_distance = weekly_distance * 0.20
        long_run_distance = weekly_distance - (
            interval_distance + tempo_distance + PARK_RUN_DISTANCE
        )

        if long_run_distance > 28:
            excess_distance = long_run_distance - 28
            long_run_distance = 28
            interval_distance += excess_distance / 2
            tempo_distance += excess_distance / 2

        current_date = START_DATE + timedelta(weeks=week)
        row = [
            current_date.strftime("%Y-%m-%d"),
            "",  # Monday
            int(interval_distance),  # Tuesday
            "",  # Wednesday
            int(tempo_distance),  # Thursday
            "",  # Friday
            int(PARK_RUN_DISTANCE),  # Saturday
            int(long_run_distance),  # Sunday
        ]

        writer.writerow(row)

        if (distance_before_recovery == 0):
            next_week_distance = weekly_distance * (1 + INCREASE_RATE)
            if next_week_distance > weekly_distance * (1 + MAX_INCREASE_RATE):
                next_week_distance = weekly_distance * (1 + MAX_INCREASE_RATE)

            weekly_distance = next_week_distance