Running in Kolkata during Durga Puja is a study in coexistence. The city does not pause for joggers, and joggers cannot reasonably ask it to. The research on training disruption during major festival weeks is sparse, but the practical evidence — from cohorts of Kolkata runners polled informally over multiple seasons — is consistent. Volume drops. Sleep shifts. Pace becomes secondary to staying upright in a crowd.
This guide synthesises what is defensible about training during the five days of Puja, drawing on published research on heat acclimatisation, sleep disruption, and exercise consistency, alongside observed patterns from Kolkata's running community. The aim is not to insist that you protect your training programme. It is to outline the trade-offs so you can make an informed choice.
What the calendar and the climate dictate
Durga Puja typically falls in late September or October, depending on the lunar calendar. The climate in Kolkata during this window remains warm and humid: average maximum temperatures of 32 to 34 degrees Celsius, relative humidity often above 75 percent, and the monsoon's tail still producing intermittent showers in early October. The India Meteorological Department's long-period averages confirm this pattern.
Heat-humidity load on the body
Research published in journals including Medicine and Science in Sports and Exercise has consistently documented that wet-bulb globe temperatures above 28 degrees Celsius elevate the risk of exertional heat illness, particularly during sustained running. Kolkata in October frequently exceeds this threshold during the morning hours after sunrise and almost certainly during the afternoon. Heart rate at any given pace runs 10 to 15 beats per minute higher than in cooler conditions.
The pandal-and-crowd variable
Beyond climate, the four main Puja days — Saptami through Dashami — bring crowds that materially alter the running environment. Major roads near pandals in Bhowanipore, Kumartuli, North Kolkata, and Salt Lake see foot traffic that begins in the late afternoon and continues past midnight. Running these areas during peak hours is not a question of pace; it is a question of physical access. The Running Lab archives include similar logistical guidance for other Indian festival cities.
How to time runs around the Puja week
Empirically, the windows that work are early morning and late night, and even these need adjustment during Puja.
The pre-dawn window
Between approximately 4:30 and 6:30 am, foot traffic from Puja-related activity is minimal. The roads in residential South Kolkata neighbourhoods — Jodhpur Park, Lake Gardens, parts of Ballygunge — are typically clear. The Maidan and Rabindra Sarobar remain usable for loops. Temperatures at this hour in October average 24 to 26 degrees, considerably more tolerable than the daytime peak. A 2017 review in Sports Medicine concluded that early-morning training in tropical climates produces lower heart-rate drift compared to afternoon sessions.
The late-night window
After midnight on weekdays of the Puja, foot traffic in residential areas drops sharply. The trade-off is sleep disruption. Cumulative research, including a 2019 systematic review in the Journal of Sleep Research, has shown that fragmented or shortened sleep over consecutive nights reduces aerobic performance and recovery markers. If you are training for a November marathon, prioritise sleep over a late-night run.
Adjusting training volume and intensity
The honest answer is that most Kolkata runners reduce volume during Puja week, and the research on detraining suggests that a single week of reduced volume — provided it does not exceed two weeks — has minimal effect on aerobic fitness.
What the detraining literature shows
A 2000 paper by Mujika and Padilla in Sports Medicine reviewed multiple studies on short-term training cessation and found that VO2 max remained stable for 10 to 14 days of reduced training, provided intensity was preserved on the days that running occurred. Practically, this supports cutting Puja-week volume by 30 to 50 percent while retaining one or two quality sessions early in the morning.
A defensible Puja-week template
For a runner peaking at 60 km per week, a 30 to 35 km Puja week, with one tempo run on Panchami (5 to 7 km at threshold), easy 8 km runs on Saptami and Ashtami pre-dawn, a rest day on Navami, and a 12 km long run on Dashami morning, fits the available evidence on training maintenance. The STRIDD plan generator can produce a similar customised week if you input Puja dates as a constraint.
Hydration, fuelling, and the festival diet
Puja food is not a small variable. The shift toward fried items, sweets, and shared meals is unavoidable for most Kolkatans. The research on dietary disruption during training is limited but suggests that short-term shifts in macronutrient distribution have less effect on endurance performance than total energy availability.
Practical fuelling guidance
If you are running 8 to 12 km in the morning on a Puja day, the festival food consumed later in the day is unlikely to derail training. Total energy intake usually exceeds expenditure during Puja, which means glycogen stores are well-stocked. Hydration is the more practical concern: humidity-driven sweat losses are high, and Puja-related sugar-heavy drinks do not substitute for plain water and electrolyte fluids. See the nutrition section for more.
Stomach considerations
Street food during Puja includes a range of items prepared and stored outside controlled food-safety conditions. Acute gastrointestinal illness can derail a week of training. The research on traveller's diarrhoea and analogous food exposures suggests caution with raw chutneys, ice from unverified sources, and food that has sat at ambient temperature for hours. Hot, freshly prepared items carry lower risk. The heat and monsoon guide covers parallel hydration concerns during Indian summers.
Air quality during Puja
Air quality in Kolkata during Puja is variable. CPCB data shows that AQI in Kolkata in October typically ranges from 100 to 200, in the moderate to unhealthy-for-sensitive-groups bands. This is materially better than NCR winters but worse than Bengaluru or coastal cities.
What this means in practice
For most healthy runners, October AQI in Kolkata permits outdoor training, particularly in the pre-dawn window when traffic emissions are lower. Runners with asthma or chronic respiratory conditions should monitor daily values and may need to reduce duration or shift to indoor training on the worst days. Use the STRIDD calculators to track training paces consistently across venues.
Choosing races and goals around Puja
If your goal race is the Kolkata 25K in mid-December or the TCS World 10K in May, Puja week is not a peak phase — it is a maintenance week. If your goal race is a November marathon, Puja can fall in your peak block, and the trade-offs are sharper.
Race-calendar planning
For runners with a November marathon, consider front-loading your highest mileage in early September and treating Puja week as a planned step-back. This aligns with conventional periodisation: high-volume weeks followed by reduced-volume weeks every three to four weeks. The events page lists Indian race dates that you can plan against. Picking races outside the Puja-peak window simplifies the trade-off.
The available evidence supports running through Puja week at reduced volume, preserving intensity on the days you do run, prioritising pre-dawn windows for both heat and crowd reasons, and managing food and hydration with practical caution. Performance is unlikely to suffer materially. The cultural and social value of being present at Puja, for most runners, exceeds the marginal training cost.