Minimum time between two servings of whey protein isolate?

Question

The study at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3197704/ concludes (emphasize mine):

We suggest that instead of a single, large protein-rich meal, ingestion of multiple moderate-sized servings of [...] protein-rich foods over the course of a day may represent an effective means of optimizing the potential for muscle growth [...].

Question: How much time should I leave between two "servings" of whey isolate?

Context

Calculation tells me that 5 or more servings are best for me (muscle gain, 75kg, 186cm). Problem: I only eat 3 meals per day, and for various reasons I can't eat nor drink anything but company-provided water during business hours (10am-12pm, 2pm-9pm). In other words, my only free time is like 1.5 hours in the morning, 1.5 hours at lunch, 3 hours in the evening. I am afraid that 1.5 hours between two servings would be too short and would equal a single large serving, ie mostly wasted.

Answer 1

The studies linked in this article found that getting approximately 20g of protein every 3 hours stimulates muscle protein synthesis (MPS) better than getting bigger portions less often and smaller portions more often.

On a practical level, while keeping that in mind, just do what works best with your schedule. If eating every 3 hours is disruptive to your schedule, then do something else either sooner or later than every 3 hours. We’re talking about maximizing a biological process here, but it’s important to remember that MPS will still occur whether we seek to maximize it or not.

As for whey isolate specifically, it’s just one potential source of protein that a person might choose to utilize. There’s nothing wrong with multiple servings of it, but as a general rule of thumb try to get some variety in the things you consume. This will help to ensure that your body gets the various nutrients it needs to function properly.