Question

how is hyperosmosis in muscle cells counteracted during a wingate sprint?
a) by glucose transport out of the cell
b) by conversion into lactate
c) by fluid - influx into the cell
d) by conversion into fructose

Explanation:

During a Wingate sprint, muscle cells undergo glycolysis rapidly, producing lactate (lactic acid). The production of lactate helps counteract hyperosmosis (high osmolarity inside cells) by reducing the osmotic gradient—lactate formation from glucose metabolism helps manage the solute concentration, and also, the associated processes (like ion and metabolite shifts) can influence fluid balance, but the key mechanism here is the conversion of pyruvate to lactate (which helps in maintaining osmotic equilibrium by reducing the accumulation of osmotically active intermediates and also, the lactate can be transported out or metabolized, but the main counteraction to hyperosmosis in this context is via lactate production. Option a is incorrect as glucose is transported into cells for energy. Option c: fluid influx would worsen hyperosmosis (if cells are hyperosmotic, fluid influx is due to osmosis, but the question is how hyperosmosis is counteracted—lactate production reduces the internal osmolarity. Option d: glucose isn't converted to fructose in muscle cells for this purpose. So the correct answer is b.

Answer:

b) By conversion into lactate