Boost SMR for Easier Leanness
Fire up your SMR and you'll have an easier time losing fat and keeping it off. Here's how.
"Burn fat while you sleep!" That's been the promise of a dozen sketchy infomercial products. The weird thing? We already do. We burn calories all night long.
You already know about BMR or basal metabolic rate. That's the energy (calories) your body uses to keep basic functions like breathing, heartbeats, and cell maintenance going when you're awake but just sitting around. But not many people think about SMR or sleeping metabolic rate – the number of calories you burn while in dreamland.
SMR is a subset of BMR. You don't burn as many calories while sleeping, but you burn more than you might think – only 10 to 20% fewer than when awake. An average 150-pound person might burn around 60-75 calories per hour during sleep or 480-600 calories over an 8-hour night.
The more calories you burn during sleep, the easier it is to avoid fat gain, get lean, or stay ripped. Night after night, even a small boost in SMR adds up fast.
How to Optimize SMR
1. Lift Weights
This one is easy for us. The more muscle you have, the higher your BMR and SMR. Even when you're asleep, muscle still needs energy for maintenance and repair, especially if you're a lifter. The more muscle you've built, the more your body must spend to keep it going overnight.
What kind of numbers are we talking about? Roughly, for every 10 pounds of iron-built muscle you've gained, you'll burn 50-60 additional calories overnight. Per hour, it's a small uptick, like 2-3 calories, but it adds up. Add 20 pounds of new muscle tissue, and you'll burn 100-120 extra calories per night. Add that to your higher waking BMR, and you're an energy-churning machine.
And don't forget muscle protein synthesis (MPS), which is active overnight. MPS is the process where your body builds new proteins to repair and grow muscle tissue. So, if you hit the weights regularly, the energy-hungry MPS process further fires up SMR.
2. Eat Protein Before Bed
If you eat anything before bed, the digestion process bumps SMR. But protein is king.
A study from the Journal of the International Society of Sports Nutrition found that eating 30 grams of casein protein 30 minutes before bed increased overnight energy expenditure by 4-8% compared to eating nothing – roughly 20-40 extra calories over 8 hours. Protein also increased next-morning resting metabolism by 5-10%, hinting at a carryover. Comparatively, the boost from 30 grams of carbs was under 3%, and fats barely moved the needle.
A related study used lifters and 40 grams of pre-bed casein. Overnight fat oxidation went up, and SMR increased by about 50-70 calories total versus a placebo. Finally, Trommelen et al. found that 40 grams of pre-sleep protein boosted overnight metabolism by 6-10%, tied to muscle repair.
As for protein types, casein, particularly micellar casein, reigned supreme and greatly outperformed whey. Micellar casein is a slow-digesting protein, making it a standout for nudging up your SMR. Its unique structure – clumping into micelles in your stomach – means it releases amino acids gradually over 6-8 hours, perfectly syncing with sleep. This slow burn keeps your metabolism active longer through digestion and muscle repair.
Given the data, it makes sense to move some of your daily protein intake to 30 minutes or so before bed. However, solid foods make this tricky because some protein sources also contain a lot of fat or carbs. The studies use protein powders. Just have a scoop or two of MD Protein (Buy at Amazon) mixed with water. That'll provide 22-44 grams of protein, including a big dose of SMR-boosting micellar casein.
3. Other SMR Boosters
- Part of SMR involves body temperature regulation. Sleeping in a cooler room makes your body work harder to stay warm, burning a few extra calories, maybe 30-50 more per night. In studies, room temp was 60-67 °F.
- Dehydration slows metabolism, even at rest. Drinking enough water during the day keeps your cells efficient overnight. No direct SMR studies here, but resting metabolism drops 2-3% when dehydrated, and sleep is no exception.
- Deep, uninterrupted sleep ramps up growth hormone release, which drives fat metabolism and repair. Fragmented sleep cuts this short, lowering SMR. A Journal of Clinical Sleep Medicine study found poor sleepers burned 10-20% less overnight than solid sleepers. The biggest cause of poor sleep? Magnesium deficiency. Make sure your levels are optimal by taking 400 mg of the chelated form before bed. The Elitepro Vital Minerals (Buy at Amazon) formula contains that amount.
