Table 5.

Associations of Physical Activity With Metabolite Groups, Calculated Using Enrichment Analysis, in Samples of Participants From the Nurses’ Health Study (1989–1990), Nurses’ Health Study II (1996–1999), and the Health Professionals Follow-up Study (1993–1995)

Metabolite Group	Multivariable Modela		Multivariable Model Further Adjusting for BMIb,c
	Enrichment OR	P for Enrichmentd	Enrichment OR	P for Enrichmentd
Cholesteryl esters	2.98	0.14	6.19	0.05
Phospholipids	1.69	0.25	2.46	0.14
Glycerolipids	1.40	0.26	0.79	0.44
Sphingolipids	0.50	0.59	0.86	0.43
Amino acids	1.36	0.35	0.80	0.57

Abbreviations: BMI, body mass index; OR, odds ratio.

^a Permutation was performed within joint strata of sex (female, male) and case status in the original study (yes, no). The enrichment OR was calculated from the 2 × 2 table of metabolites (in/out of group vs. significant/nonsignificant). Determination of whether individual metabolites were significantly associated with physical activity (nominal P < 0.05) was obtained using linear regression analysis adjusting for age (years; continuous), case-control status (case, control), case-control study nested within the 3 cohort studies (16 categories), smoking status (never, past, or current smoker), fasting status at blood collection (yes, no), alcohol intake (g/day; continuous), Alternative Healthy Eating Index score (0–100; continuous), total energy intake (kcal/day; continuous), BMI (continuous), and intakes of fatty acids (linolenic acid, α-linolenic acid, eicosapentaenoic acid, docosahexaenoic acid, oleic acid, stearic acid, and trans- fatty acids).

^b BMI is calculated as weight (kg)/height (m)².

^c Permutation was performed within joint strata of sex (female, male), case status in the original study (yes, no), and BMI (<25, 25–29, ≥30).

^d The P value for enrichment was based on 10,000 permutations to simulate the distribution of the enrichment OR under the global null hypothesis that no metabolite is associated with physical activity.