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What would you do?
You've been training hard for six weeks. You feel a cold coming on. You've got a session booked tomorrow.
Do you:
You eat well. You train hard. You take your vitamins.
But every few weeks you're floored.
A cold that knocks you out for four days. A sore throat that drags on all week. That heavy, fuzzy feeling where you're not quite sick but definitely not right.
You've started to just accept it. "I've always been like this."
You haven't always been like this. You've just been filling your cup for long enough that it feels normal.
Your immune system is not separate from your lifestyle. It's a direct reflection of it. Every stressor in your life fills the same cup. Work deadlines. Intense training. Poor recovery. Undereating. Your body doesn't separate them. It just sees outgoings.
When the cup overflows, your immune system is the first thing that gets cut. Not your ability to function at work. Not your energy to train. Those feel more urgent. So your body keeps them running and lets your defences down instead.
Here's what fills the cup faster than most people realise.
Recovery. This is the big one. Poor recovery directly suppresses your immune function. People sleeping under 7 hours are four times more likely to catch a cold than those getting enough. And it's not just sleep. No rest days, no deload, no downtime. Your body never gets the signal to repair. It just keeps spending.
Chronic stress. When stress stays elevated for too long, cortisol starts suppressing your immune system instead of protecting it. A stressful week is fine. Six stressful months in a row is a different thing entirely. Your body stops fighting off illness and redirects everything to just surviving the stress.
Undereating. This one catches people out the most. Especially if you're in a fat loss phase. Extreme calorie restriction is directly linked to impaired immune function and higher infection risk. Drop calories too low for too long and your body starts cutting non-essentials. Immune function is near the top of that list.
Overtraining. Hard training is a stressor. The right kind. But stack too many hard sessions with not enough recovery and you're actively suppressing your immune system. More is not always more.
Any one of these sustained long enough will do it. You don't need all four.
The fix is not complicated. It just requires you to take recovery as seriously as you take training.
1. Recovery is not a reward. It's the work.
Most people treat rest days like something they earn after a good week. They're not. They're where the adaptation happens. Where your body repairs, rebuilds, and recharges its defences.
If your week has no easy days, no proper sleep, no downtime, you are not being disciplined. You are just letting the cup overflow without ever emptying it.
Aim for 7 to 9 hours of sleep. Build in at least one full rest day. Every few weeks, back off the intensity for a few days. Not because you're being soft. Because that's how the body works.
2. Eat enough to support what you're asking your body to do
A moderate calorie deficit is fine. Chronic undereating is not. If you're training hard and eating as little as possible, something will break. It's usually your immune system first, then your performance, then your motivation.
If you're always tired, always hungry, and always getting sick, eat more.
3. Manage the full stress load, not just the gym
Your body doesn't know the difference between a brutal deadlift session and a brutal day of back-to-back meetings. Both add to the same cup.
On high stress weeks, train less intensely. Not less consistently. A 60% effort session beats a missed session. And it doesn't fill a cup that's already close to overflowing.
I'll be honest. I learned this one the hard way.
Back in 2017 during my bodybuilding prep, I was training hard, eating low, sleeping badly and building a business at the same time. I thought I was being disciplined. I was constantly picking up injuries. Always run down. Always one bad week away from getting sick.
I didn't connect the dots at the time. I thought it was bad luck. It wasn't. My body was doing the maths and I was always in the red.
Most people I work with now are in the same place I was then. They just don't see it yet.
Now when a client tells me they're always getting sick I don't need to investigate for long. I already know what the picture looks like. Training too hard, eating too little, recovering too poorly, stress too high.
Fix the recovery. The immune system sorts itself out. Every time.
Want to go deeper?
And just for fun 👇🏼
See you Tuesday,
— Akash
The answer
Most people pick A. It feels like the disciplined choice. It's not. Pushing through when your immune system is already low makes you sicker for longer and costs you more time than a rest day ever would. B is better but incomplete. C is the right answer. A lighter session keeps the habit, tells your body you're listening, and getting to bed early is where the actual recovery happens.
