Combination of amylopectin and chromium form improves energy storage and reduces muscle fatigue in rats during exhaustive exercise

This study evaluated the effects of amylopectin (A) and chromium (Cr) forms alone or in combination on energy storage, muscle fatigue-related biochemical markers, and expression of peroxisome proliferator-activated receptors (PPAR-γ) and glucose transporter-2 and -4 (GLUT-2 and GLUT-4) in rats during exhaustive exercise. Thirty-five male Wistar rats were divided into 5 groups (n = 7) as follows: 1) exhaustive exercise (E); 2) E+A; 3) E+A+chromium picolinate (CrPic); 4) E+A+chromium histidinate (CrHis), and 5) E+A+CrPic+CrHis. Rats received 0.0316 g of amylopectin and 11.06 µg of elemental Cr kg$^{-1}$ body weight given as CrPic and CrHis per day. The mean duration of exercise differed (55 ± 1.15 vs. 76 ± 1.91) between groups (P < 0.05). Blood glucose level was significantly reduced in the E+A+CrPic+CrHis group compared to the E group. The E+A+CrPic+CrHis group was superior in terms of increasing muscle and liver glycogen contents and blood insulin concentration and of decreasing serum lactate concentration (P < 0.05 for all). However, A and Cr did not alter GLUT-2, GLUT-4, and PPAR-γ expressions. In conclusion, A in combination with supplemental Cr enhanced energy-yielding nutrient conservation and reduced muscle fatigue in exercised rats. They can also help prevent racehorse performance and disability problems.