I don’t have a specific dosage for you, but I do know that as infants are weaned they begin to display gut bacteria that can degrade resistant starch , so they can make use of it. Also, mother’s milk comes prepackaged with a type of prebiotic known as human milk oligosaccharide, so babies can definitely benefit from prebiotics.
Do infants “need” resistant starch? Maybe. Their gut bacteria still need to eat, and RS has been shown to be a good source of food for bacteria in adults and infant pigs. Yep, pigs. You’re not one, but the omnivorous pig is a fair proxy for humans. Infant pigs who eat resistant starch enjoy increased calcium, zinc, iron, and phosphorus absorption compared to infant pigs eating digestible starch.
Here’s what I’d do: once the baby’s getting the majority of his calories from solid food rather than milk/formula/breastmilk, start including tiny amounts of RS. I’m talking tiny – like a quarter teaspoon at a time – just to see how he reacts. If you’re up for chewing food (which is “weird” but also pretty normal on a global, historical scale), try a small amount of chewed green banana.
Actually, scratch that. Green bananas are awful unless incorporated into smoothies. Why not stick to whole foods that taste good? Once your kid starts eating starches, you can give him small amounts of cubed cold leftover potatoes. 100 grams of cooked and cooled potato has about 5 grams of RS, so start small.
If the kid doesn’t have any problems like extreme amounts of gassiness, constipation, diarrhea, or other symptoms of an upset stomach, the RS is probably beneficial and definitely harmless. Just go slowly.
Great question. For those who don’t know, a tempo run is a sustained effort at or around the anaerobic threshold, also known as the lactate threshold. You’re at maximum aerobic/fat-burning capacity and juuust starting to flirt with obtaining significant energy from the anaerobic pathway. Tempo runs are tough but manageable – they’re “comfortably hard.” They’re intense enough to push training adaptations without being so unpleasant that you quit before it’s over.
There are actually different kinds of tempo runs. Most people, when they use the term, refer to 5-10 mile runs at close to race speed. But sprinters do them too. Sprinters do tempo runs for active recovery and building/maintaining the aerobic base (yes, even sprinters need an aerobic base). For a tempo day, they might run a total of 2000 meters in 100s, 200s, or 400s. Easy-ish pace, enough to get their heart rate up a bit. They look a lot like sprints, only at 60-75% intensity.
Tempo runs can get you into trouble. First of all, there’s not a switch that blocks the aerobic pathway and turns on the anaerobic pathway. It doesn’t work like that. You’re always burning bits of everything and there are no hard barriers, so it’s very easy to go harder than you’d intended and get into almost pure sugar burning territory. That’s cool if you want to do that to improve your fitness and you accept the consequences, but I’d advise against using such a run on a regular basis for fat burning /body composition alterations/health maintenance.
Don’t get me wrong: if you do them right, tempo runs are great for burning body fat. But they burn lots of other stuff, too. And if you do too many of them with too little rest in between, you’ll burn out. Tempo runs got me into trouble. My absolute intensity was significantly different than the rest of the population, but my relative intensity wasn’t necessarily higher than an enthusiastic amateur runner. I just did too much .
I’d say sprinting still gets the nod. Sprinting isn’t so much a pure burner of calories in a mechanistic sense (although it does that too). What it really does is get the “furnace” going better than almost anything else, allowing you to make better use of energy substrates without them turning into fat, and increases insulin sensitivity so glucose replenishes glycogen without requiring as much insulin. Plus, a recent study found that two minutes of sprinting resulted in the same 24 hour oxygen consumption (a marker of post-exercise metabolism) as 30 minutes of steady state endurance training (akin to a tempo run). So yeah, a tempo run is good, but sprints are just so much more efficient.
Make sure you’re doing tempo runs right and they can be very helpful. If you find yourself bonking and craving sugar/carbs afterwards, you’ve probably ventured far afield of the aerobic pathway and should go easier next time. Or just focus on sprints for fat loss and do tempo runs for fun.
Thanks for reading, folks. Got any comments or advice for the readers who asked today’s questions? Leave ‘em in the comment section!