Body weight, food consumption and white adipose tissue weight.

<p>Body weight, food consumption and white adipose tissue weight.</p

The marrow fat volume at the distal end of the femur as assessed by two-dimensional histomorphometry (A) and a micrograph of marrow fat (B) at 25 weeks of age.

<p>The black arrow indicates bone tissue, and red arrow shows marrow fat in micrograph. All values are presented as the mean ± SEM. * <i>p</i><0.05 vs. all; † <i>p</i><0.05 vs. L-Sed; # <i>p</i><0.05 vs. L-Ex.</p

The bone mechanical properties of the rats at 25 weeks of age.

<p>Maximum breaking force (A) and stiffness (B) were lower in OLETF rats. In contrast, energy to fracture was not different between genotype. All values are presented as the mean ± SEM. * <i>p</i><0.05 vs. all; † <i>p</i><0.05 vs. L-Sed; # <i>p</i><0.05 vs. L-Ex.</p

Blood analysis related to diabetes.

<p>The blood glucose (A), plasma insulin (B) and serum leptin (C) levels were significantly greater in O-sed rats than in the LETO rats, but it was attenuated by exercise. Serum adiponectin (D) levels were increased by exercise. All values are presented as the mean ± SEM. * <i>p</i><0.05 vs. all; † <i>p</i><0.05 vs. L-Sed; # <i>p</i><0.05 vs. L-Ex.</p

The bone volume at the distal end of the femur as assessed by two-dimensional histomorphometry at 25 weeks of age.

<p>All values are presented as the mean ± SEM.</p

Insulin-stimulated phosphorylation of Akt was significantly improved in liver of OLETF rats after voluntary exercise.

<p>At 15 weeks of age, insulin (0.5 U/kg BW) or saline was injected via the portal vein following overnight fasting. At 5 min after the injection, liver was taken under anesthesia. Insulin-stimulated phosphorylation of Akt at threonine 308 (C) and serine 473 (D) was significantly increased in the liver of OLETF rats after exercise, as compared with sedentary condition. Basal (exogenous insulin-naïve) Akt phosphorylation in the liver was not different between the voluntary exercise and sedentary OLETF rat groups. The protein expression of Akt did not differ between voluntary exercise and sedentary condition in the liver of OLETF rats (B). *,p<0.05; **,p<0.01 versus sedentary OLETF with saline, †,p<0.05 versus sedentary OLETF with insulin. N.S.: not significant.</p

Hyperglycemia and hyperinsulinemia in the OLETF rats were reversed by voluntary exercise.

<p>The blood glucose (<b>A</b>) and plasma insulin (<b>B</b>) levels were significantly greater in the OLETF rats under sedentary conditions (SED) than in the LETO rats on SED. There were no significant differences between the LETO and OLETF rats with respect to the effects of voluntary exercise (VE) on the plasma insulin levels. The OLETF-SED rats exhibited insulin resistance, as indicated by elevated HOMA insulin resistance index values (<b>C</b>). All values are presented as the mean ± SEM. n = 9–11 per group, *,p<0.05; **,p<0.01 versus sedentary LETO, †,p<0.05 versus voluntary exercise OLETF, ‡,p<0.05 versus voluntary exercise LETO. N.S.: not significant.</p

Exercise suppressed the lipogenic gene expression and prevented the accumulation of TG and activation of JNK in the liver in the OLETF rats.

<p>The triglyceride content in the liver (<b>A</b>) was significantly lower in the voluntary exercise (VE) OLETF rats than in the sedentary (SED) OLETF rats. Consistent with the decreased triglyceride levels, the mRNA expression of <i>Srebp-1</i> (<b>B</b>) and <i>Scd-1</i> (<b>C</b>) was significantly decreased in the OLETF-VE rats. It is known that lipid accumulation in the liver increases the JNK activity. The total JNK amount was significantly increased in the OLETF rats compare with that observed in the LETO rats (<b>D</b> and <b>E</b>). The phosphorylation of JNK was significantly increased in the liver in the OLETF-SED rats compared with that observed in the LETO-SED rats (<b>D</b> and <b>F</b>). After 20 weeks of exercise, the activated JNK content in the liver decreased in the OLETF rats. The protein levels of JNK and p-JNK were normalized to that of actin. All values are presented as the mean ± SEM. n = 7–11 per group, *,p<0.05; **,p<0.01 versus sedentary LETO, †,p<0.05; ††,p<0.01 versus voluntary exercise OLETF. ‡,p<0.05; ‡‡,p<0.01 versus voluntary exercise LETO. N.S.: not significant.</p

Effects of voluntary exercise on the iNOS mRNA expression and S-nitrosylation of Akt and IRS-1 in the liver in the OLETF rats.

<p>The mRNA expression of iNOS was significantly increased in the liver in the sedentary OLETF rats (<b>A</b>). The S-nitrosylated Akt levels were significantly increased in the liver in the sedentary (SED) OLETF rats (<b>B</b>). Voluntary exercise decreased the S-nitrosylated Akt levels in the liver in the voluntary exercise (VE) OLETF rats compared with those observed in the OLETF-SED rats. Similarly, S-nitrosylation of IRS-1 was also increased in the liver of SED OLETF rats (<b>C</b>). The degree of S-nitrosylation was evaluated using a biotin switch analysis. All values are presented as the mean ± SEM. n = 9–11 per group, **,p<0.01 versus sedentary LETO, †,p<0.05; ††,p<0.01 versus voluntary exercise OLETF. N.S.: not significant.</p

Additional file 1 of Association between objectively measured physical activity and body mass index with low back pain: a large-scale cross-sectional study of Japanese men

Table S1-B: Sensitivity Analysis, Table S2-B: Sensitivity Analysis. Sensitivity analysis of the results of the combined “None/Sometime (intermittently)” and “All the time (Persistent)” group of LBP compared to the “All the time (Persistent)” group of LBP. (DOCX 24 kb