Fig. 4: Regional glycogen depletion and repletion patterns in muscle after higher intensity exercise.
a T2W image in the axial view showing regions with the three types of glycogen repletion. The estimated initial rate (\({R}_{{{\rm{rep}}}1}^{{{\rm{initial}}}}\) and \({R}_{{{\rm{rep}}}2}^{{{\rm{initial}}}}\)) maps in b phase I and c phase II, respectively, for the multiphase recoveries (types b and c) in subject #15. d T2W images with overlay showing different types of repletion along the length of MG and soleus for a representative subject (#23). The measured glycogen levels as a function of time in muscle regions with type a (e), type b (f), and type c (g) kinetics, as indicated in (a). h–j Group average (n = 14, 7, 9, and 12 subjects for type a slow, type a rapid, type b, and type c, respectively) of glycogen levels as a function of time in regions with type a, b, and c kinetics. k Group analysis (n = 14, 7, 9, and 12 subjects for type a slow, type a rapid, type b, and type c, respectively) of glycogen depletion amount \({\Delta [{{\rm{Gly}}}(0)]}_{{{\rm{dep}}}}^{{{\rm{ex}}}}\) for the three types of kinetics. Data are presented as mean ± SD. Statistical significance was determined using two-tailed unpaired Wilcoxon rank-sum test. p < 0.05 were considered statistically significant. Correlation and linear regression between glycogen depletion and initial repletion rates of phase I (l) and glycogen repletion over 3 h post exercise (m) (n = 14 subjects). The data points were indicated using the same color coding as in (a) for the respective types of kinetics. The gray shadows indicate SD in (h–j) and 95% CI in (l, m). Source data are provided as a Source Data file.
