How to Work Out Your Ideal WPI 90 Serving Size

There is no magic number on the tub. "One scoop" is a starting point, not a prescription. The right WPI 90 serving size depends on how much you weigh, how hard you train, and what you are actually trying to do with your body. Get it right and every gram is working. Get it wrong and you are either leaving results on the table or spending money on protein your kidneys are flushing out. Here is how to find your number.

How much protein do you actually need per day?

This is where everything starts. Before you pour a single scoop, you need a daily protein target - and that target is personal.

The research is pretty consistent on ranges:

Notice that fat-loss phases sit at the higher end of the range, not the lower. That's because extra protein preserves lean muscle while you are eating less. If you drop calories without keeping protein up, you lose muscle along with fat - which makes the whole cut less useful.

Quick example: an 80 kg person training four days a week with a muscle-building goal needs roughly 144 to 176 g of protein per day (80 kg x 1.8 - 2.2 g/kg).

How do you figure out the right number of scoops?

Once you have your daily target, the math is simple: subtract what you already eat from whole food sources, and make up the rest with WPI 90.

Here is a realistic example:

• Target: 160 g protein per day
• Breakfast: 3 eggs + Greek yogurt = 30 g
• Lunch: chicken breast + rice = 45 g
• Dinner: salmon + vegetables = 40 g
• Total from food: 115 g
• Gap to fill: 45 g

A standard WPI 90 scoop delivers around 27 g of protein per 30 g serve. So two scoops covers that 45 g gap comfortably, with one after training and one earlier in the day when food protein is lighter.

That is the key insight: your serving size is not "one scoop because the label says so." It is the amount that closes the gap between your food and your goal.

Does your serving size change as your goal changes?

Yes, and this is where a lot of people fall behind. They find a serving size that works during one phase and stick with it forever, even when their training or body changes significantly.

Think of WPI 90 as a tool that adjusts with you, not a fixed habit. Reassess your daily protein needs every 6 to 8 weeks, especially if your training load or body weight has shifted.

Does it matter when you take each serving?

Timing matters less than total daily protein, but spreading servings out does make a practical difference. Research consistently shows that muscle protein synthesis responds best to doses of around 20 to 40 g at a time. Much above that in one sitting and the extra protein isn't used more efficiently - it just gets processed normally as energy or excreted.

For most people, that means:

• One serve post-training (the window when your muscles are primed to use it)
• One serve at another protein-light point in the day - morning, mid-afternoon, or before bed

If you need three or more scoops a day to hit your target, spread them across different meals rather than blending them all into one massive shake. The article on protein timing and absorption gets into the detail of exactly when each window matters most.

What about body weight versus lean body mass?

The targets above use total body weight, which is the simplest starting point. Some coaches prefer to calculate protein based on lean body mass (total weight minus fat mass), particularly for people with a higher body fat percentage. The logic: fat tissue doesn't need protein for repair or growth the way muscle does.

In practice, for most people training regularly, the total body weight method gets you close enough. If you want to be precise and you know your body fat percentage, use your lean mass figure and aim for the higher end of the range (2.0 - 2.4 g per kg of lean mass).

Can you take too much WPI 90?

For healthy adults with functioning kidneys, consistently high protein intakes are well-tolerated. The concern about protein "damaging kidneys" applies mainly to people who already have kidney disease - not to healthy people eating more protein. That said, eating protein well above what your body can actually use for muscle repair or synthesis is not a smart use of money or calories.

A practical ceiling for most people: 2.4 to 2.6 g per kg of body weight per day. Going beyond that rarely produces better results and starts eating into your budget for other nutrients.

Frequently asked questions

Is one scoop of WPI 90 enough per day?

It depends on how much protein you get from food. For someone eating a lot of meat, fish, eggs, and dairy, one scoop might be enough to close the gap to their daily target. For someone eating lighter or training hard, two scoops is more realistic. Calculate your total daily target first, then figure out how many scoops bridge the gap from your food intake.

Should I take more protein on training days?

Your protein target can stay consistent across training and rest days. Some people find it easier to eat a bit more on training days and slightly less on rest days, but the total across the week is what matters most. Consistency beats perfect timing every time.

Can I have two scoops in one shake?

Yes. Two scoops in one shake delivers around 54 g of protein. That is toward the upper end of what a single sitting can put to work efficiently, but it is not wasted - your body will still digest and absorb it. If you prefer fewer, larger shakes, that works. If you prefer smaller serves more often, that works too. Hit your daily total either way.

Does serving size change for women versus men?

Gender doesn't directly change the per-kilogram calculation, but women typically weigh less than men, so their absolute daily target is usually lower. A 60 kg woman training for muscle building needs roughly 108 to 132 g of protein per day. A 90 kg man with the same goal needs 162 to 198 g. Same formula, different numbers at the end.