As a health and exercise professional, understanding how habits form is essential to helping clients achieve long-term behavior change. New research from the University of South Australia systematically reviewed the time required to develop health habits and identified key factors that influence habit formation. Contrary to the commonly held belief that habits form in 21 days, this study finds that while habits may begin developing within two months, the process can take up to 335 days depending on various factors.

Read on to learn key findings from this study and explore how you can apply them to better support clients in building sustainable health behaviors.

The Reality of Habit Formation

So, exactly how long does it take to form a habit? University of South Australia researcher, Dr Ben Singh, says that contrary to popular belief, healthy habits take far longer than three weeks to lock down. “Adopting healthy habits is essential for long-term well-being but forming these habits—and breaking unhealthy ones—can be challenging,” Dr. Singh says. In fact, the study found that the median time to form a habit ranges between 59 and 66 days, with the average ranging from 106 to 154 days.

The important thing, says Dr. Singh, is to avoid giving up if a habit isn’t fully established after 21 days. “In our research, we’ve found that habit formation starts within around two months, but there is significant variability, with formation times ranging from four days to nearly a year. So, it’s important for people who are hoping to make healthier habits not to give up at that mythical three-week mark.”

It's important to keep in mind that, when it comes to forming habits, individual variability is significant, with habits forming in as little as four days or taking as long as 335 days. This variation is influenced by factors such as:

• The type of behavior – Simpler behaviors (e.g., drinking water or flossing) become habits faster than more complex ones (e.g., regular exercise or dietary changes).
• Frequency of repetition – The more consistently an action is repeated, the stronger the habit becomes.
• Context stability – Performing a behavior in a stable environment (e.g., always exercising at the same time each morning) increases the likelihood of forming a habit.
• Personal motivation and enjoyment – Habits are more likely to stick when individuals find them enjoyable and self-selected rather than externally imposed.

These findings highlight the importance of setting realistic expectations with clients. If they believe that habits form quickly, they may become discouraged when they don’t see immediate results. Instead, helping clients understand that habit formation is a gradual process can promote persistence and long-term success. It may also help clients to understand the types of benefits that one can expect to see more quickly compared to those that will take longer to achieve. For example, exercise has both immediate and long-term benefits. Immediate benefits include improved cognition and reduced feelings of anxiety, while it will take longer to improve cardiorespiratory fitness. Knowing what to expect and how soon can help clients tset realistic expectations.

The Four Stages of Habit Formation

Lally and Gardner proposed a four-stage framework for understanding how habits form:

• Deciding to take action – The individual sets an intention to engage in a new behavior.
• Translating intention into behavior – The person begins to act on their goal.
• Repeating the behavior – The action is performed consistently within a stable context.
• Developing automaticity – The behavior becomes ingrained and effortless.

The final stage, automaticity, is crucial for long-term adherence. Automatic habits require less willpower and conscious effort, making them more sustainable over time.

How Can Health and Exercise Professionals Apply These Findings?

1. Set Realistic Expectations

Educate clients that habit formation takes time and varies from person to person. Encourage them to focus on progress rather than perfection. Since some habits take months to solidify, help them reframe setbacks as part of the process rather than failures. Reframing can take practice (by both the professional and the client). Let’s look at an example: Your client has improved their sleep quality over the past 30 days by making changes to their bedtime routine. However, two weeks ago they traveled for business and have not been able to get back on track with their new routine. The client says they feel like a failure and can’t seem to get back on track but are still adhering to some elements of their new sleep routine. It can be easy for the client to view this as a failure, but by using good coaching skills and asking insightful questions, you can help the client find the good in the situation and to move forward. Some sample questions include: How were you able to be successful prior to traveling? What behaviors are you still doing now? What would you need to start doing now to get back on track? And what can be learned from this experience?

2. Encourage Consistency and Routine

One of the strongest predictors of habit formation is context stability. Encourage clients to integrate new behaviors into their existing routines. For example, a morning workout may be more effective than an evening session, as morning habits tend to develop more reliably.

Linking new habits to existing ones (e.g., doing body-weight exercises after brushing teeth) can help solidify behavior patterns. Here are some examples of open-ended questions you can use to explore context stability with your clients:

• What would integrating this behavior into your existing routine look like to you?
• What habit might you already have that you can link this new behavior to?
• What resources do you need to integrate this new habit?
• What time of day will be best for this new behavior?
• Where will this behavior take place?

3. Help Clients Develop Implementation Plans

Behavioral research suggests that specific implementation intentions improve habit formation. Encourage clients to plan their actions in advance, specifying when, where and how they will perform a behavior. For example, a client might say, “I will go for a 20-minute walk every weekday at 7:30 AM after my morning coffee,” or “I will prepare my gym clothes and water bottle the night before so I am ready to work out in the morning.” Figure 1 is an example of a very simple habit tracker that your clients can adapt and use based on their current goals and desired habits.

4. Focus on Enjoyable Activities

People are more likely to maintain habits when they find them enjoyable. If a client dislikes running, encourage them to explore alternative activities such as hiking, dance or strength training. Helping clients find forms of exercise they genuinely enjoy increases adherence and makes habit formation more effortless.

5. Reinforce Progress With Small Wins

Since habit formation is a gradual process, celebrating small milestones can keep clients motivated. Positive reinforcement—such as acknowledging their commitment to daily activity—can increase self-efficacy and make the habit more rewarding.

6. Encourage Self-reflection and Tracking

Encouraging clients to journal about their experiences can enhance self-awareness and habit adherence. Tracking progress (e.g., using a fitness app, calendar or simple checklist) provides tangible evidence of success and keeps clients engaged in the process.

7. Provide Long-term Support

Many public health programs focus on short-term interventions (e.g., 21-day challenges), but these may not be sufficient for sustainable behavior change. As a health professional, providing long-term coaching, accountability and support can help clients navigate challenges and maintain their habits over time.

Conclusion

The findings from this systematic review underscore that habit formation is not a one-size-fits-all process. While new habits can begin forming in two months, full automaticity may take significantly longer. Understanding the key determinants of habit formation—such as repetition, environmental stability and personal enjoyment—can help you design more effective programs.

By setting realistic expectations, fostering consistency, and providing ongoing support, you can empower your clients to develop sustainable health habits that lead to lasting behavior change.

Expand Your Knowledge

Mental Well-being Certification

Expand your expertise with the Mental Well-Being Certification. This course empowers you to incorporate mental health and well-being strategies into your training for a more integrative, self-care approach to client care. Focusing on the four pillars of mental well-being—exercise, nutrition, connection, and mindfulness—you'll gain the expertise to help clients manage stress, improve mood, and build resilience through fitness. This 20-hour certification is designed for health and exercise professionals, equipping you with the tools to confidently address mental well-being within your scope of practice. With evidence-based research and practical coaching techniques, you'll learn to support clients' mental health and well-being, foster stronger connections, and create an inclusive, supportive environment. Whether you're expanding your services or deepening client engagement, this course prepares you to meet the rising demand for mental well-being coaching in the fitness industry.

Building Healthy Habits Through Group Health Coaching

The future of the health and wellness profession combines the skills of fitness training and health coaching to help clients maintain motivation by uncovering their own strengths and skills. Health coaching in a group setting can help your clients navigate their own health and wellness by connecting with others on a similar journey. In this video training, you will learn how to run group coaching sessions and develop the skills you need to empower client motivation while building healthy habits within a community experience. Adding this unique skill set of group coaching to your current practice will help your clients navigate change and add a new dimension of growth to your business.

Improving Wellness Through Behavior Change – Course Bundle

Effect and inspire positive lifestyle change within your clients by applying behavior change strategies. Whether you are coaching clients in chronic pain or stress management, the Improving Wellness Through Behavior Change course bundle has you covered. Learn the latest techniques and strategies to work more effectively with your clients so they can establish healthy habits that last a lifetime.