Physical Activity Is Associated With Improved Glycemic Outcomes in Newly Diagnosed Youth With Type 1 Diabetes: 4T Exercise Program

Abstract

Objective: The Teamwork, Targets, Technology, and Tight Range (4T) Exercise Program evaluated physical activity patterns across the first year of type 1 diabetes diagnosis and whether physical activity was associated with changes in glucose outcomes in the 24 h following physical activity.

Research design and methods: The 4T Exercise Program started newly diagnosed youth with type 1 diabetes on a continuous glucose monitoring (CGM) system and physical activity tracker around 1 month postdiagnosis. A subset of youth opted to participate in up to four quarterly structured exercise education sessions to increase their knowledge around safe physical activity.

Results: Ninety-eight youth with type 1 diabetes (median [interquartile range (IQR)] age of 13 [12-15] years, 45% female, 44% non-Hispanic White) completed the study. Compared with sedentary days, days with ≥10 min of vigorous-intensity physical activity were associated with an increase in time in range (TIR) of 2.3% (1.4-3.2%; P < 0.001), a decrease in time above range (TAR) of 3.1% (2.2-4.0%; P < 0.001), and an increase in time below range (TBR) of 0.8% (0.6-0.9%; P < 0.001) in the 24 h following physical activity. From 1-3 months to 10-12 months postdiagnosis, the median (IQR) step count increased by 1,134 (445-1,519) steps per day (P < 0.001), while daily moderate-to-vigorous physical activity increased by 11 (2-23) min per day (P < 0.001).

Conclusions: In the 24 h following physical activity as compared with sedentary days, TIR improved, TAR was lower, and TBR remained within clinical target recommendations. For youth with new-onset type 1 diabetes, each structured exercise education session was associated with a further 0.79% increase in TIR.

Graphical abstract

Figure 1

Overall summary of daily step count (A) and daily MVPA (B) across the first year of T1D diagnosis. Study periods are separated into quartiles including 1–3 months (green), 4–6 months (orange), 7–9 months (purple), and 10–12 months (pink) postdiagnosis. Box plots represent median and IQR; whiskers extend to ±1.5 IQR, and data points represent the spread beyond the upper limit.

Figure 2

The 4T Exercise Program participants’ glucose TBR (<70 mg/dL), TIR (70–180 mg/dL), and TAR (>180 mg/dL) in the 24 h following exercise compared with sedentary days. A: Relative change data are reported as mean (95% CI) percent change in glucose TBR (red), TIR (green), and TAR (yellow), denoted by ◊ and colored bars. B: Absolute change data are reported as mean and 95% CI. The exercise categories are as follows: short moderate-intensity activity (10–29 min/day), sustained moderate-intensity activity (≥30 min/day), and vigorous-intensity activity (≥10 min/day).