Are 30-Day Challenges Good or Bad for Changing Habits?

By Chris Carmichael,
Founder and Head Coach of CTS

For many people, January 1^st was the start of a new 30-day challenge. Maybe it was Dry January, a commitment to abstaining from alcohol for a month. For people looking to change their eating habits, maybe it was Whole 30, a commitment to eating only whole foods for a month. Those looking to change exercise habits might be starting 30 straight days of cycling, walking, running, or pull ups. But do these 30-day challenges actually work? Are they a good model for creating lasting behavioral changes?

The Pros of 30-Day Challenges

As the old story goes, a journey of a thousand miles starts with a single step, so at some level committing to a 30-day challenge can be positive in that it’s a start. More than that, it’s a kickstart because it’s a commitment to a period of heightened focus on a particular behavior. Some of the positive aspects of 30-day challenges include:

Defined Timeframe

One of the biggest problems with New Year’s Resolutions is that they are open-ended. Your long-term goal might be to consume less alcohol, eat more whole foods, or exercise more consistently, but the notion that you’ll never drink again, never eat processed food again, or never skip a workout can be overwhelming. A 30-day challenge is manageable timeframe, which improves compliance and consistency, which are crucial for creating lasting change.

Long enough to start seeing results

There is no magical timeframe for creating lasting habits. There’s a misconception that it takes 21 days to change a habit, which comes from plastic surgeon Dr. Maxwell Maltz’s observation­–included in the 1960 book “Psycho-Cybernetics”–that it took a minimum 21 days for patients to adjust to the changes to their bodies. That was later complicated by the idea that it took 21 days to create a new habit, and then 90 days of consistent practice to make it permanent. Proponents of the 90-day part often reference this study, which stated the average length of time to make a new behavior automatic was 66 days (21 + 66 = 87, so close enough). But the individual variability was huge, ranging from 18 days to 254 days. Regardless of the timing, we know that positive reinforcement is a key to making a new habit stick. A 30-day challenge may be long enough for a some people to start experiencing positive feedback from their new habit, which reinforces the motivation to stick with it.

With training goals, 30 days might not really be enough to see substantial physiological changes, particularly for athletes who are already pretty fit and are using a challenge to adjust training. For new athletes, 30 days will be sufficient to see measurable changes in performance (but be prepared for the rate of improvement to slow as you get more fit). In either case, however, one month is a good timeframe for resetting training behaviors (consistency, scheduling, hydration, recovery, sleep, etc.).

Opportunity to Assess and Adjust

A 30-day challenge often features a more intense focus on one area of life or fitness than is sustainable–or necessary–long term. However, that temporary intensity serves a purpose by causing a significant departure from your normal patterns. The end of a 30-day challenge is an opportunity to assess what’s working and what’s not, and what aspects of this new habit need to be adjusted to make it more sustainable and integrated into your lifestyle.

Take the fitness challenges, like riding or running every day for 30 days. These can be helpful in the short term for helping athletes make riding or running second nature, to the point it feels strange not to. That doesn’t mean training 7 days a week, 52 weeks a year, is going to be the best preparation for your goal events. But, now that you are so accustomed to riding more often, the adjustment of inserting rest days and easy days is easier.

For nutrition challenges, like Whole 30 or a month of eating entirely plant-based foods, the end of the challenge is an opportunity to ease the restrictions and make choices about which foods you want to add back into your daily diet.

The Cons of 30-Day Challenges

While there are some compelling reasons why 30-day challenges can be beneficial for athletes or anyone looking to change their habits, there are also some potential downsides.

May lead to rebound behaviors later

Depriving yourself of something you really want is not a recipe for long-term success. A 30-day challenge may help you kickstart a behavior change that you truly believe in, but it’s not going to work if you’re counting the days until you can go back to what you were doing before. The classic examples are Dry January and no-sugar challenges. For some people, they can be pathways to long-term reductions in alcohol or added sugar, but for many others they are just thinly veiled weight loss challenges or a perceived counterbalance to overindulging during the holidays. When February hits, prohibition is over and people enthusiastically (and often over-enthusiastically) return to their previous behaviors. And for people dealing with alcohol addiction or eating disorders, these challenges do nothing to address the underlying causes for their struggles.

May be too disruptive to be successful

The intensive focus of a 30-day challenge may be good for you but wreak havoc on the people around you. If your fitness challenge disrupts the schedules for other people in your household, or if your nutrition challenge means you are eating entirely different meals than your family, then it’s going to be hard to integrate into your lifestyle long term. This is one of the obstacles dietitians run into with people struggling with obesity. The person’s social and family environments often reinforce food choices and eating behaviors that are conducive to obesity, so the individual trying to make a change may also face pressure to conform to the habits of the people around them.

Making a 30-Day Challenge Work for You

If you are a goal-oriented athlete working with a coach or from your own training plan, be careful to consider whether a 30-day challenge will enhance or hinder your sport-specific goals. Challenges like Dry January or one focused on getting at least 8 hours of sleep for 30 straight nights are likely to support your training, recovery, and weight management goals. Be more careful about restrictive dietary challenges, because supporting your training with adequate total energy intake is crucial for making progress. Similarly, talk with your coach or carefully consider how or whether to implement a 30-day riding or running challenge. The goal would be to create daily habits and routines, which means that “riding every day” could take the form of normal training rides (endurance, intervals, etc.) and very light spins or bike commutes that reinforce the habit but allow for adequate recovery. “Riding every day” shouldn’t mean “ride hard for 30 days straight”.