Enzyme concentration: More enzyme molecules result in a higher vmax. Temperature: Increasing the temperature typically increases reaction rates up to an optimum point, beyond which the enzyme may denature. pH: Each enzyme has an optimal pH range within which its activity is maximized. Cofactors and coenzymes: These can enhance enzyme activity and consequently affect vmax. Inhibitors: Competitive inhibitors do not affect vmax, while noncompetitive inhibitors decrease it.