I did not start with the science. I started with people.
For 28 years I have coached entrepreneurs and real estate agents. For the last 7 of those years I ran the same two ideas with more than 500 of them. Work in sprints, placed at the hours you are sharpest. And never do it alone.
The ones who did both produced more. I could see it. I could not prove why.
So I went and read the research. It turns out the two things I kept seeing in the field have names, effect sizes, and decades of studies behind them. This page is what I found, what it says, and what I built with it.
Two patterns showed up over and over.
First, people who committed to a daily action in front of someone else did the action. People who committed to it in private did it about half the time.
Second, people who did their hardest work in a bounded block, at the time of day they told me they were sharpest, got more of it done and quit less.
I want to be straight about what that is and is not. It is 7 years of watching 500 people up close. It is not a controlled study. The people who hire a coach are already the ones who act. I never saw what the same person would have done without me. And "produced more" was units and commission, which I could count, but I never had a control group to count against.
That is why this page exists. My observations are the reason I built UpSprint. The research below is the reason you should trust it.
The research. Your body runs on rhythms shorter than a day. Hormones pulse. Alertness rises and falls. Sleep cycles every 80 to 100 minutes. Nathaniel Kleitman, who co-discovered REM sleep, proposed in 1963 that this rest-and-activity pattern continues while you are awake.
Sixty years of attention research adds the practical part. Performance on demanding work drops with time on task. Deliberate breaks restore it. In a 2011 experiment, brief interruptions that pulled people off a task and back on prevented the decline entirely (Ariga and Lleras, Cognition). A 2022 meta-analysis found breaks reliably cut fatigue and restore energy, and that longer breaks help performance more than short ones (Albulescu et al., PLOS ONE).
A break only counts if it changes what you are doing. Stand up. Move. Look at something far away. Email is not a break.
In UpSprint. A 75-minute focus block followed by 15 minutes of real recovery. Long enough to get past setup and into the work. Short enough to defend from a calendar. The research does not fix the exact number, so you can change it. What it does fix is the shape: a bounded block, a real break, then again.
The research. Your chronotype is when your body wants to be awake. It is genetic. A study of 697,828 people tied it to specific clock genes (Jones et al., 2019, Nature Communications). Morning types run about 3 hours ahead of evening types on melatonin timing. It shifts with age, and most adults land in the middle.
The part that matters for work is called the synchrony effect. In 2021 researchers measured working memory, attention, and learning at people's preferred and non-preferred times of day. Performance was measurably better at the preferred time, and the brain was measurably more excitable and more plastic (Salehinejad et al., Nature Communications). The gap between your body clock and your work clock has a name too, social jetlag, and it costs sleep and performance every week (Roenneberg et al., 2019).
This is what I was seeing in my clients. The ones who put prospecting at 7 AM and the ones who put it at 4 PM were not lazy or disciplined. They were early and late types doing the same thing at their own peak.
In UpSprint. Your first sprint of the day belongs in your peak window. Morning types: within 2 to 4 hours of waking. Evening types: late afternoon into evening. Everyone else: late morning. Put your hardest commitment there and protect it from meetings. Keep your wake time the same 7 days a week. That one habit is the biggest lever on social jetlag there is.
The research. In the most cited study of expert performance, K. Anders Ericsson studied elite violinists. The best of them limited effortful, focused practice to roughly 4 hours a day. They did not out-grind their peers. They rested more and slept more (Ericsson, Krampe, and Tesch-Romer, 1993, Psychological Review).
This study gets misquoted as "experts work in 90-minute bursts." It does not say that. It says hard focus has a daily ceiling and the people who reach the top respect it.
In UpSprint. Four cycles a day. When the fourth ends, the day's deep work is done. This is not a wellness feature I added for balance. It is the part of the method with the best evidence behind it.
The research. About 47 percent of people who intend to do something never do it (Sheeran, 2002). The fix with the strongest track record is an if-then plan: "At 8:00 AM, I will open the CRM and call 5 expired listings." A meta-analysis of 94 studies and more than 8,000 participants found this one habit produced a medium-to-large improvement in follow-through, a d of 0.65, over having a goal alone (Gollwitzer and Sheeran, 2006). The effect is largest for discrete, time-bound actions. It has held up through the replication crisis that took down much of the rest of the field.
The mechanism is simple. You hand the decision to the trigger. When 8:00 arrives you do not decide whether to call. You already did.
In UpSprint. Every morning you name one action and the time you will do it. UpSprint reminds you at that time, not at a generic hour. You mark it done or not. Thirty days of that is a record of who you are becoming.
The research. Psychologists have known since 1965 that the presence of another person speeds up simple and practiced work (Zajonc, Science). Being watched, or expecting to report, raises effort. Voluntary commitments with something at stake improve follow-through (Rogers, Milkman, and Volpp, 2014, JAMA). In one small study, people who wrote their goals and sent weekly progress reports to a friend hit 76 percent of them, against 43 percent for people who kept goals in their heads (Matthews, 2015, 267 participants).
The ADHD community has known this longer under the name body doubling. The first academic survey, 220 people, found 186 of them were more likely to finish a task with another person present (Eagle et al., 2024). In 2025 the first controlled trial tested it. Adults with ADHD worked 27 to 30 percent faster with a partner present. The partner did not have to be human. An AI double worked as well as a person, and the people who found a human stressful preferred it (Ara et al., 2025).
This is the second thing I saw for 7 years. The client who told me the plan on Monday and told a group what happened on Friday did the plan. The client who told only me did it half the time.
In UpSprint. Live coworking rooms where you sprint next to other people. Small circles where a known group holds you to your daily commitment. Familiar peers make accountability feel like support. Strangers make it feel like a standard. You get both.
I will not tell you your brain runs on a 90-minute clock. Kleitman proposed that idea and 60 years later no one has confirmed it in awake humans. Sub-daily rhythms are real. A fixed focus timer is not one of them.
I will not quote you a productivity percentage from a vendor survey. The body doubling companies publish numbers like 152 percent. Those are self-reports from their own customers. I built a company on this method and I still will not use them.
I will not call my 500 clients a study. They are the reason I built this. The research above is the reason it works.
Every sprint and every commitment inside UpSprint is logged. Completion rate. Cycles per day. Whether you were in a room or alone. In 2027 I will publish what the data says, including the parts that do not flatter the method.
Until then, here is the deal. Complete your daily action at least 3 days a week for 30 days. If it did not move your work, you get your money back.