Hi friends,

You know that saying, "When it rains, it pours"? Well, that's what the last few weeks have felt like.

About two weeks ago, my dad had a stroke–don't worry, he's fine. He's a tough bastard. I would know after all the ass-whoopings he gave me as a kid.

Then last week, Kris and Amara flew to the US to see Kris' parents, where Amara ended up in the ER because she wasn't breathing normally. By the time she got to the hospital, her breathing rate was twice what it should be for her age. That marked the start of a 1.5-day hospital stay because the doctors couldn't tell what was wrong–all the tests they ran (flu, COVID, RSV) came back negative–but she was still struggling to breathe without oxygen and medication. They suspect it might have been some type of pneumonia or underlying asthma symptoms flaring up. ¯\_(ツ)_/¯

Anyway, Amara's good now – well, except for the fact she has to carry around this inhaler-contraption that looks like a bong (yes, I'm making a joke to deal with the whole thing, leave me alone).

But if you've noticed my absence in your inbox, that's why. I haven't had the mental capacity to do much. I would say we'll be back to normal moving forward, but at this point, I'm afraid to tempt fate, so let's just get to this week's email.

**A quick note before we start: I'm not sharing the above for sympathy. I'm sharing it because, well, it's my fucking newsletter and I can write what I want. But two, when I sent out the yearly feedback form in December, an overwhelming majority of you pointed out that you enjoyed the personal stuff I used to share, and it's something I want to get back to (don't worry, they won't always be this dark, I hope).

Most people screw this up
​(How to track your progress properly)

If you've been reading my content for a while, you'll know how I feel about the idea that the scale is a bad way to track progress (it's a dumb idea - the scale is a great way to track progress).

However, it's not the only thing that matters, and if you only rely on the scale — well, you're fucking yourself.

Here's an example of what I mean.

This is Kristin. She's an endocrinologist in her early 40s who started working with me 16 weeks ago.

Kristin wasn't new to working out; she'd been doing Barre for 5 years, but wasn't following a structured lifting program designed with her goals in mind––build lean muscle and "get a concrete plan instead of bouncing around too many fitness plans/recommendations."

Over the 16 weeks, she's gotten visibly leaner, gained muscle, and gotten stronger in the key lifts we were tracking.

Based on the last paragraph, you might expect her weight to have decreased.

Actually, no. In fact, her weight has stayed exactly the same.

Yet, her waist measurement has dropped by 1.5" while her arms, legs, and glute measurements have increased slightly.

In my experience, this is almost always an indicator of body recomposition (losing fat while gaining muscle).

But we don't have to lean on my "trust me, bro" – we can actually gutcheck Kristin's progress by using some of the research that's available.

In 2018, Woolcott and Bergman published a body fat estimation equation developed from data on over 12,000 adults in the National Health and Nutrition Examination Survey and validated against DEXA. [1]

Unlike BMI, which only uses height and weight, their equation uses height and waist circumference, and it breaks down like this:

-> 64 - (20 × height/waist circumference) + (12 × sex)

(Where sex = 0 for men and 1 for women.)

We have Kristin's height (5'8") and her waist at both time points. When we plug in her numbers, the equation estimates her body fat went from about 29% to 26.5% — a drop of about 2.5%.

Now, I should point out that the equation has a margin of error of about ±3.5%. Meaning, the equation could overestimate by up to 3.5 percentage points or underestimate by up to 3.5 percentage points.

Looking at Kristin's starting photo, I'd put her closer to 25%. Likewise, her most recent photo suggests she's probably sitting around 22–23%. Both of those fall within the equation's margin of error.

Regardless, the actual % doesn't matter too much. Whether you use the equation's numbers (29% > 26.5%) or my estimate (25% > 22%), the change is roughly the same: about 2.5–3 percentage points.

Since her weight has remained stable at 136 lbs (~62 kg), that works out to roughly ~3.5 lbs (~1.6 kg) of fat lost.

And since her weight didn't change, that fat had to be replaced by something, so:

• ~3.5 lbs of fat lost.
• ~3.5 lbs of muscle gained.
• Net scale change: zero.

If you're skeptically inclined, you might be thinking two things: Can we really use waist measurements to predict fat mass changes? And could someone really gain 3+ lbs of muscle in four months?

The research would suggest yes.

On the first point:

In a DEXA-tracked study of over 300 adults, Lahav and colleagues found that changes in waist circumference closely mirrored changes in fat mass, with a correlation of r = 0.84. A correlation of "1.0" would mean a perfect match between the two variables. [2]

And to address the muscle gain estimate:

​In another article, I referenced a meta-analysis by Hagstrom and colleagues looking at muscle gain in untrained women after 15 weeks of resistance training. The average increase was 1.45 kg (3.2 lbs), with a range of 0.4–3.3 kg (0.9–7.3 lbs). Kristin's estimate of 3.5 lbs sits comfortably within what a woman new to lifting could gain.

Just to be clear: the numbers above are estimates. Kristin may have gained a bit less muscle and lost a bit less fat, or gained a bit more muscle and lost a bit more fat, but the estimates are directionally correct. Her weight held steady while her body composition changed, and that's enough to be confident a recomp took place.

The main lesson is this: If you're trying to achieve any type of body composition change, you should be tracking your progress in more than one way–regular photos, body measurements, and even strength gains. One metric could be skewed, but if the others are heading in the right direction, progress is happening. In Kristin's case, while her scale weight was all over the place, her waist measurement continued to decrease pretty consistently over the same timeframe; her body composition improved, and her measurements were also changing in the right places, all while she continued getting stronger in the gym.

So, how should you track progress?

Weigh daily, but focus on the longer-term trend

If you weighed yourself today, could you be confident that's your true weight? Probably not, because it's one weigh-in and, on its own, it doesn't tell you anything.

But if you weigh the same for the next two weeks, you can be more confident that's how much you actually weigh because you have multiple data points saying the same thing.

But that's just the first step. Once you have your daily weigh-ins, you'll very quickly realise there's a lot of noise. So you need a way to isolate the signal–that is, the actual trend from randomness.

The most common approach is a 7-day average, which is ok, but it still sucks because it can be easily skewed by a few outliers. I personally like using an 18-day average because it better smooths fluctuations and gives you a more accurate representation of the trend.

Just to illustrate the above: the graph below shows Kristin's daily scale weight (grey dots), the 7-day average (blue line), and the 18-day average (red line).

The 7-day average is doing a pretty poor job of dealing with Kristin's weigh-ins––someone whose weight can fluctuate a lot in a short timeframe.

If you were basing calorie adjustments on the 7-day average, you're going to end up on a calorie rollercoaster–decreasing calories one week, increasing them the next, only to decrease them again in the third week, only to realise you didn't even have to make those adjustments in the first place.

However, if you look at the 18-day average, the line is much smoother and does a much better job of showing that Kristin's weight hasn't really changed. For example, look how much the blue line peaks and dips between 21st December and 18 Jan. Meanwhile, the 18-day line hums along smoothly, unperturbed by the noise.

The key point: How you analyse your data is more important than the data itself. For scale weight, you should use the longer-term trend to inform any dietary changes, not a single weigh-in. Whether you choose a longer averaging window or prefer the 7-day window, just make sure you're not making adjustments based on an overreaction from short-term noise.

Take body measurements

Body measurements give you additional data points you can use alongside your scale weight. If your weight's been holding steady, but your waist measurement is decreasing, and your arm/leg measurements are increasing consistently over time, that can be a sign that fat loss is occurring alongside muscle growth.

Ideally, you would track your waist, arms, legs, hips, and chest. But if you want to keep it simple, your waist measurement is the one I'd prioritise for a fat loss goal. If the goal is recomp or muscle gain, track the body parts you care about. For instance, I don't care about leg growth, but I care about arm growth because I'm a bro at heart, so I take arm measurements once per week, and only measure legs once every month or two.

Progress photos

Yes, I know. You don't like taking progress photos––get over it. Over weeks and months, progress photos are probably the strongest proof that your body composition is changing. And alongside the scale and body measurements, they ensure that any changes you're making to your nutrition or training actually make sense.

Additionally, you see your body every day, so even if changes are happening, they can be hard to notice. However, comparing your progress photos today with those from a month ago will almost certainly show changes (as long as you're not fucking around).

How often you take progress photos is up to you, but at a minimum, you should take them once per month, if not at least every other week. This allows you to capture changes in body composition more quickly.

Training

To gain (or retain) muscle, you need to be strength training. But going to the gym and half-assing your training won't cut it. You need to be training hard enough for your muscles to respond. Specifically, this means lifting weights that take you close to failure on every set. Once that's in place, you need to continue increasing the load, reps, or both to keep training intensity high.

But if you're not tracking your training, you can't really know if any of those things are true. How much did you lift last week or the week before that? And are you lifting more today than a month ago?

The good thing is that there are only three things you need to track to know if your training is producing results:

• The weight you lifted
• The reps you completed
• And how hard each set was (using reps in reserve or RIR)

Additionally, you want to keep your training somewhat consistent week to week so you can actually track the above. If you're constantly 'switching things up', you have no way of knowing if you're actually getting stronger.

Here's what I recommend:

• Pick 4-5 compound exercises. These exercises should include a squat pattern, a hinge pattern, a press, a pull, and optionally one exercise for a body part you enjoy training or want to focus on.
  ​
• Keep the compound exercises the same for 8-12 weeks. That wasn't a typo. You need enough time with an exercise to progress it effectively. If you're changing movements too soon, you won't know whether you're making progress.
  ​
• Use the accessory exercises for most of your variety. For instance, if one of your compound exercises was the leg press and one accessory was a bicep curl, the leg press would stay the same throughout the 8-12 weeks, but you could change the bicep curl every 4-6 weeks to another variation. This gives you the best of both worlds–you're able to track your progress through the leg press and get some variety through the bicep curl variations.

If your goal is just to lose weight, the scale can be a great tool if used correctly. But if you're reading this, I'm assuming you care more about improving your body composition. In that case, expanding the toolkit to include measurements, progress photos, and training logs means you're making better decisions, resulting in more fat loss and better muscle and strength retention.

–Aa

Sauces:

1. Relative fat mass (RFM) as a new estimator of whole-body fat percentage ─ A cross-sectional study in American adult individuals, Woolcott OO, Bergman RN. 2018

2. Resistance training as a key strategy for high-quality weight loss in men and women, Lahav Y et al. 2026

3. The effect of resistance training in women on dynamic strength and muscular hypertrophy: a systematic review with meta-analysis, Hagstrom AD et al. 2020

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