Table 5.

Physical Activity

Study	N	Age range/mean	Diagnoses	Non-SCD Control	Relevant Outcome Measures	Related to Physical Impairments and Function
Buchowski et al. 200244	28	14–18 years/15.6 ± 1.5 years	SCA	Yes	Accelerometer	Participants with SCD had decreased physical activity level compared to controls Physical activity level (SCD: 1.32 ± 0.10; controls: 1.48 ± 0.12); p = 0.001 Adjusted physical activity level (SCD: 1.32 ± 0.10; controls: 1.41 ± 0.01); p = 0.040
Karlson et al. 201758	30	8–18 years/13.9 ± 2.9 years	HbSS HbSC HbSβ0 HbSβ+	No	Actiwatch 2 movement counts	Mean physical activity was light intensity 97.7% of days (386 ± 143 counts/min Overall peak physical activity (2820 ± 1118 counts/min) Moderate (42.4% of days) Vigorous (57.4% of days) Children with SCD presented with decreased peak physical on pain days compared with non-pain days
Melo et al. 201859	50	6–18 years/12.02 ± 3.63 years	HbSS	Yes	Accelerometer	Participants with SCD presented with lower physical activity compared to controls Decreased vector magnitude counts (SCD: 3967142 ± 1743719; controls: 5194904 ± 2098832); p < 0.01 Decreased vector magnitude count per minute (SCD: 764 ± 297; controls: 1096 ± 1096); p < 0.01 Less vigorous physical activity minutes per day (SCD: 3.6 ± 4.1; controls: 7.8 ± 7.4); p < 0.01 Less moderate physical activity minutes per day (SCD: 19.2 ± 11.9; controls: 27.1 ± 13.8); p < 0.01) Lower MET (SCD: 1.71 ± 0.4; controls: 1.87 ± 0.39); p = 0.04 Fewer total steps (SCD: 51010 ± 19600; controls: 59105 ± 22650); p = 0.04 Lower total energy expenditure (SCD: 1015 ± 516 Kcal; controls: 2404 ± 1308 Kcal); p < 0.01
Singhal et al. 199748	16	16.1–20.1 years/18.0 ± 1.1 years	SCD	Yes	Heart rate monitor	Participants with SCD had decreased physical activity compared to controls More low activity (SCD: 3.6 ± 1.2 mJ; controls: 4.8 ± 1.5 mJ); p = 0.033 Less high activity (SCD: 10.2 ± 5.8 mJ; controls: 5.7 ± 3.4 mJ); p = 0.022 Lower total daily energy expenditure (SCD: 13.8+/−4.9 MJ/d; controls: 0.5+/−2.2 MJ/d); p=0.034 Decreased physical activity as measured by the ratio of total daily energy expenditure to resting metabolic rate (SCD: 2.2 ± 0.8; controls: 1.5 ± 0.3; p = 0.006) and total energy expenditure minus resting metabolic rate (SCD: 7.5 ± 4.9 MJ/d; controls: 3.5 ± 2.2 MJ/d; p = 0.01)

Abbreviations: N = number of participants with sickle cell disease; SCA = Sickle Cell Anemia; SCD = Sickle Cell Disease; MET = metabolic equivalent of task. Results are reported as mean ± standard deviation, except where noted otherwise.