How Knack applies behavior science

Planning makes a difference.

You are motivated. Otherwise, you wouldn’t be here. The difficult part: the “feeling” of motivation swings distantly from the goals you want.

But, we can supplement your motivation through planning, a more cognitive process that helps you translate motivation into action.

Wanting is “I should train more.” Action planning is “Monday, Wednesday, Friday, one hour, after work at my local gym.” Note that this contains the day, the time, the place, and the length. Plans written that way get carried out more often.^1,2 Another way to think about this is as a cue, or an if-then automatic process. “If it’s Monday after work, then I’m training.”

See how this strategy translates across domains. Take the job search. You don’t just “want” a job. You decide when you’ll send five applications, when you’ll go over the twenty questions you might be asked, and how you’re going to reframe your “greatest weakness” into something you’re “working on.” In other words, you give yourself the structure to be successful. In the lifting world, the equivalent is planning how often you’re going, how long, and when.

This type of planning is also effective because it gives you something to check yourself against. Across 122 exercise and diet programs, self-monitoring against a target (say, how many times you train per week) stood out as an effective strategy for supporting behavior.³ So, this is why we at Knack make such a big deal out of planning and setting a goal.

But what happens when life kicks you and you fall off? The research has identified two types of plan in this space: the action plan, and the coping plan, which is what you do when the action plan breaks.^4,5 Having both is the key.

Our app will prompt you to set a coping plan to complete your profile. For example, “If I’m too busy this coming week, I’ll go 3 days instead of 4 days, where I combine the work of two of the days so I’m still covering all bases.” When this coping plan is defined, as you can guess, it’s more likely to be followed through. This helps you avoid the “all or nothing” trap, or doing nothing at all that week.

Beyond the science and in my practice, the folks I’ve known who are still training after year one, two, five, twenty, are the ones with very adaptive coping plans. Ask anyone training that long if they’ve hit their action plan every week of the year. The chances are very low that they did, but they stuck with it. Knack will encourage you to do the same.

Confidence, checked.

Planning is great, but the success of those plans is higher if you feel confident that you can follow through.⁶ So, after you create an initial plan within our app, you are asked how confident you are that you’ll do it in the following weeks. If your confidence is low, you’re prompted to edit your plan into something that brings your confidence level up. This technique is used in motivational interviewing, which is a collaborative conversation between coach and client to evoke intentions to change. This is done by resolving ambivalence, or the tug-of-war between wanting to change and wanting to stay the same. Resolving your ambivalence to change can increase the success rate of the changes you want to make.⁷

See the wins in your actions themselves.

As a society, personal records and transformations get a lot of attention and are treated as the main “wins.” But, there are bigger wins, and they happen to be the wins that get personal records and transformations.

Examples of wins that matter more:

Bandura called these mastery experiences, which are experiences where you succeed in a difficult task and build self-efficacy to do it again and better next time. The theory has held up for close to fifty years. “Doing” is the best evidence about yourself. Self-talk or someone’s encouragement can argue with you; lived actions cannot. And one caveat that gets forgotten, make the wins appropriately challenging enough to cost you just a little bit.^8,9

See your strengths.

Start thinking about setbacks differently. Missing sessions, having to bring your weight down, or not seeing progress as fast as you’d like are opportunities to see personal strengths and opportunities for growth. When you see it that way, you’ll achieve more as you expect more of yourself next time and stick at it longer.^10,11,12,13

If you see the setback at face value, you might see failure. Look at it differently, and realize that “failure” is a privilege. Intentionally shifting how you think about something for the better is called cognitive reappraisal, a strategy that builds your resilience and your ability to overcome difficult tasks.^14,15

“Why?” beats “What?”

In the app you pick one: Strength, Muscle, Strength and Muscle, or General Fitness. That tells our optimizer what to build. But, to complete your profile, we invite you to dig deeper to your “Why?”

This reason sits a level above. The concern isn’t whether you’re motivated versus unmotivated—It’s....what actually drives you? Reasons you’ve chosen for yourself (like being strong, feeling better) tend to be stronger, as that better predicts training months later. Reasons that are pressure in disguise (I’d feel guilty, someone expects me to) are good at getting you started, but doesn’t hold up as well as the reason you picked yourself.^16,17,18,19 These forms of motivators are known as external regulation and introjected regulation. Additionally, your own, specific reasons for strength training, such as improved daily quality of life (mood, energy, capability), beat general “for better health”.²⁰ So, be specific.

It’s also important to think about the immediate benefits of strength training rather than just the distant, long-term goal.²¹ “I’ll look better in a year” is not necessarily what keeps you going day-to-day. “I feel better on the days I lift” can help more. Look for the joyful parts of strength training and daily benefits as well.

Choosing for yourself is part of the mechanism

Yes, asking for your preferences and personalization needs helps us sell you the app… But, it also happens to be the mechanism for behavior change support. Programs that fit you and what you’re ready for help you stick to it.²² This is why the app asks about your preferences and why every exercise has a swap button.

Have a good time on purpose

Remember, strength training doesn’t have to suck. Of everything we’ve talked about, having a good time to help with your consistency is often the least respected, yet the best supported. When we recommend exercises, if you know something feels terrible for you, swap it. Make your own training more enjoyable. Find your intrinsic motivation. De-emphasize what you don’t want to emphasize. Emphasize what you do. Go at your own pace.^22,23 Put on some good music. Go with a buddy. You’re more likely to come back to an enjoyable experience.

We decided against streaks early

First thing we have to acknowledge: streaks work in some contexts. In one study, six hundred adults were split between a control group and three gamified step programs: all three beat the control for the twenty-four weeks they ran.²⁴ But, when you take the games away, most of the advantage leaves with it (though the competitive arm was still ahead three months later).

Here’s the other side. In one study, everyone did the same strength exercises, then chose what to do next. The streak log was manipulated by the scientists. The people whose log showed a broken run picked another strength exercise less than the people who had a clean run, DESPITE having done the exact same work.²⁵ The kick too: the drop gets bigger when you hold yourself responsible for the break, and smaller when the streak can be repaired. You could also feel guilty that you’ve “fallen off,” and that could affect your desire to be consistent. Of most concern, streaks may even undermine intrinsic motivation for the activity you want to engage in.²⁶ Overall, that’s why we’re staying clear of this. Look forward to what you can still win instead and practice self-compassion, which may help with continuing training.^27,28

Also, the streak counter would just function as a second goal on top of your training,²⁵ and it can be ended by a work trip or vacation. That’s not reflective of your true progress. Drop the gimmicks and let your lived progress speak for themselves.

Rigidity can kill your plan

It’s called exercise-related all-or-nothing thinking. When you miss a session on a rigid plan, you may feel behind or like you failed. Maybe you felt this before: if you can’t do the whole session, why do any of it. Twenty-seven adults who tried to train and couldn’t make it stick had rigid ideas about what a session should look like, laying the groundwork for skipping entirely.²⁹

So, we initially hand you a rigid-looking plan, assuming the scenario that life is perfect and you will follow every session. But, we designed for those times life is not perfect. We’ve designed our calendar and optimizer to let you move things around according to your life without sweating the details. Take the messy marathon over the sprint any day, that gets more results.

When I miss a session, how effective is the merged session?

First thing we will absolutely own: you don’t get two sessions’ worth out of one session. But, we estimate you can get roughly 70–80% of the results, based on practical coaching experience and the dose–response curve below.³⁰ This percentage will be higher if you’re newer, and lower if you’re more experienced. To make this happen, we help you prioritize the high-yield compounds, trim the isolations down to just a few, and reorganize your training so that you at least hit each muscle twice a week.

If you do find yourself having to go less often or using different equipment. Always remember, especially go hard on those days. Recent science has been indicating that intensity and training close to failure is a huge equalizer beyond just how much work you’re doing.^31,32