The Science behind the Activity Score
Physical activity is one of the most important determinants of health, longevity, and quality of life. The Activity Score is built upon a strong foundation of scientific evidence, bringing together the most impactful aspects of daily movement to provide a clear, actionable measure of your physical engagement. By understanding the science that underpins each contributing factor, anyone can see how even modest changes in daily habits have measurable impacts, helping to unlock a healthier, more active life.
1. Steps
What is it?
The total number of steps taken in a day—capturing walking, running, and general ambulation.
Why it matters:
Daily step count is among the simplest and most widely studied measures of physical activity. Even modest increases in step count are associated with substantial reductions in mortality and chronic disease risk.
What the science shows:
Each additional 1,000 steps per day reduces your risk of death from any cause by 6–15% (Banach et al., 2023).
Averaging 7,000–10,000 steps per day is an evidence-based goal, but significant benefits start as low as 4,000–6,000 steps/day compared to being sedentary (Banach et al., 2023, Hansen et al., 2022; Paluch et al., 2021).
People in the highest step-count group have up to a 40–50% lower risk of premature death, cardiovascular disease, diabetes, and certain cancers compared to those with the lowest step counts (Paluch et al., 2022; Del Pozo Cruz et al., 2022; Hall et al., 2020).
2. Active Hours
What is it?
The number of hours in a day during which any movement is detected—from light activity like walking to more intense exercise.
Why it matters:
Distributing activity across more hours each day is uniquely beneficial. Prolonged sedentary periods are linked to higher health risks. Regular movement throughout the day supports healthy metabolism, circulation, mood, and brain function..
What the science shows:
People with ≥8 active hours per day have up to a 30% lower risk of developing metabolic syndrome compared to those with <4 hours active (Kim et al., 2013)
Each additional hour where movement occurs (even light movement like slow walking, standing, or household chores) lowers odds of abnormal blood sugar by 11–14% (Healy et al., 2007; Smith et al, 2024).
Spreading movement throughout the day (versus being active only in one block) is associated with measurable improvements in cognitive performance in older adults (Smagula et al., 2022).
3. Active Calories
What is it?
The total calories burned during periods of movement or structured exercise.
Why it matters:
Active calorie expenditure is a direct proxy for energy output, which underpins weight management and supports metabolic health. Higher activity-related energy expenditure improves cardiovascular fitness and lowers risk of obesity, diabetes, and heart disease.
What the science shows:
Each additional 1,000 calories burned per week through physical activity is linked to a 20–30% reduction in risk of cardiovascular disease and premature death (Lee & Paffenbarger, 2000).
Every 10 MET-hour per week of physical activity (about 2.5 hours of brisk walking or ~700 kcal for an 80-kg person) is linked to a 13% reduction in type 2 diabetes risk (Aune et al., 2015).
A negative or balanced energy equation—burning as many or more calories than consumed—is fundamental for preventing obesity and its associated diseases (Piercy et al., 2018).
4. Intense Activity Duration
What is it?
The cumulative time spent in moderate to vigorous physical activity (MVPA) such as brisk walking, running, cycling, or intense sports—activities that significantly raise your heart rate and breathing.
Why it matters:
Short bursts of higher-intensity activity yield outsized health benefits, improving cardiovascular fitness, muscle strength, and metabolic health more efficiently than lower-intensity activity.
What the science shows:
Meeting WHO activity guidelines (150 min/week moderate or 75 min/week vigorous) is linked to a 31% lower risk of all-cause mortality, 33% lower risk of heart disease, and 25–35% lower risk of type 2 diabetes (WHO, 2020; Arem et al., 2015; Kyu et al., 2016; Jeon et al., 2007).
Even as little as 10 minutes/day of vigorous activity improves aerobic fitness and lowers all-cause mortality by 6-13% compared to doing none (Saint-Maurice et al., 2022; Swift et al., 2018).
Greater amounts—over 300 min/week of moderate activity—provide up to 39% lower risk of all-cause mortality and lead to further gains in cardiorespiratory fitness, blood pressure, and mental health (Arem et al., 2015; Piercy et al., 2018).
5. Extended Inactivity
What is it?
The total amount of time spent in sedentary behavior —sitting, reclining, or being inactive—especially when these periods last longer than 30–60 minutes without a break.
Why it matters:
Prolonged, uninterrupted inactivity is an independent health risk—even if you otherwise exercise. Breaking up sitting time is critical for metabolic health, cardiovascular function, and longevity.
What the science shows:
Sitting for more than 8 hours per day is associated with a 20–40% higher risk of all-cause mortality and heart disease, even after accounting for exercise (Ekelund et al., 2016; Biswas et al., 2015).
People who spend more time sitting—especially in prolonged, uninterrupted bouts—tend to have larger waist circumference, higher blood pressure, and greater risk of type 2 diabetes, independent of total physical activity levels (Healy et al., 2008; Dunstan et al., 2012).
Standing up or walking for 2–3 minutes every 30 minutes can improve blood sugar and insulin levels by ~20–25% and reduce fatigue (Dunstan et al., 2012; Bailey et al., 2019).
6. Floors Climbed
What is it?
The number of floors (or flights of stairs) climbed throughout the day.
Why it matters:
Stair climbing is a vigorous physical activity, requiring greater energy output and muscle engagement than walking on level ground. It is a practical way to improve cardiovascular health, muscular strength, and functional fitness.
What the science shows:
Climbing more than 55 flights per week is associated with 29% lower risk of death compared to climbing less than 10 flights per week (Paffenbarger et al., 1993).
Stair climbing interventions in inactive adults have been shown to increase cardiorespiratory fitness by 10–16% over 8 weeks (Boreham et al., 2005).
Each additional flight of stairs climbed daily is associated with a reduced risk of atherosclerotic cardiovascular disease—including heart attack and stroke (Song et al., 2023).
Conclusion
The Activity Score is grounded in decades of rigorous research, translating complex evidence into meaningful guidance for everyday life. By monitoring key dimensions of movement, the score offers a transparent, science-based roadmap for improvement. Whether optimizing for personal health, designing applications, or guiding organizational wellness, these foundations ensure that every step taken is a step toward better health outcomes.
References
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