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So, you’ve been grinding in the gym, eating everything in sight, and finally starting to fill out that T-shirt. But now you’re wondering… “Should I be doing cardio?” On one hand, you don’t want to lose those hard-earned gains. On the other, you don’t want to end up gasping for air every time you climb a flight of stairs.
Here’s the deal: cardio is important, even if you’re a skinny guy trying to bulk up. But there’s a right way to do it that won’t sabotage your muscle growth. In fact, when done correctly, cardio can actually help you build muscle by improving recovery, heart health, and overall fitness. The key is to strike the right balance.
Let’s break down how you can incorporate cardio for skinny guys without torching your gains—and maybe even make it work in your favor.
1 Low-Intensity Cardio for Skinny Guys
If you’re a skinny guy, the last thing you want is to burn off the few calories you’re managing to stuff down every day. The goal is to do just enough cardio to keep your heart and lungs in good shape without turning your gains into cardio fuel.
The Fix: Stick to low-intensity, steady-state cardio (LISS) for 2–3 sessions per week, 20-30 minutes each. Think walking on an incline, cycling at a moderate pace, or a light jog. You want your heart rate elevated, but you shouldn’t feel like you just ran a marathon. This way, you’re burning fat and boosting cardiovascular fitness without eating into your muscle gains.
Why it works: Low-intensity cardio taps into fat stores for fuel and spares your glycogen (carbs) and protein (muscle). You’re not pushing yourself into the red zone, so it’s much easier to balance with your strength training.
2 Best Time for Cardio When Building Muscle
You’re lifting heavy to get bigger, so don’t let cardio steal the spotlight from your strength training. Doing intense cardio before your lifting sessions is like eating dessert before dinner—it just ruins everything. You’ll deplete your energy and have nothing left for those big lifts, which are the real muscle builders.
The Fix: Schedule your cardio sessions on rest days or after your lifting workouts. This way, you can still get the cardio benefits without it interfering with your strength training. If you do cardio after lifting, keep it short and sweet—think 15-20 minutes max of moderate intensity.
Why it works: When you lift first, your body prioritizes strength and muscle-building. By doing cardio afterward, you burn extra calories without compromising your lifting performance. On rest days, a little cardio can actually help with recovery by increasing blood flow and helping your muscles recover faster.
3 Why Cardio Aids Muscle Recovery
The main reason cardio has a bad rap for skinny guys is because most people treat it like a calorie-burning competition. But for you, cardio’s main purpose should be to improve recovery and overall health, not to torch through your already-hard-to-come-by calories.
The Fix: Treat cardio as active recovery rather than a fat-burning session. Think about it as a way to get the blood flowing, clear lactic acid from your muscles, and improve your cardiovascular system so you can lift harder and recover faster. Walking, swimming, or light cycling are perfect for this.
Why it works: Gentle cardio promotes blood circulation, which helps deliver nutrients to your muscles and removes waste products like lactic acid. This speeds up recovery, so you’re ready to go hard again in your next lifting session.
4 Eat More on Cardio Days
Here’s the harsh truth: if you’re a skinny guy and you want to stay in muscle-building mode, you need to replace the calories you burn during cardio. Otherwise, you’ll end up in a calorie deficit, and muscle growth will come to a screeching halt.
The Fix: On cardio days, up your calorie intake by 200-300 calories (or more, depending on the intensity and duration of your cardio). Focus on adding extra carbs and protein—the fuel your body needs to repair and grow muscle after workouts.
Why it works: You’re already in a calorie surplus (hopefully), so adding a few extra calories on cardio days ensures you’re still in a muscle-building zone, not burning off those gains. Plus, the extra carbs help refill your glycogen stores, giving you more energy for your next workout.
5 Use HIIT Sparingly
High-intensity interval training (HIIT) has its place, but it’s like spice—too much of it, and things get out of control fast. HIIT can be great for improving endurance and torching fat, but it also puts a lot of stress on your body and eats into your recovery time.
The Fix: If you love HIIT, limit it to 1 session per week and keep it short—15-20 minutes of all-out effort is more than enough. Use it as a finisher after a lower-intensity workout, or on a day when you’re not lifting.
Why it works: HIIT is intense and burns a lot of calories in a short amount of time, but it also taxes your muscles and central nervous system. By keeping it short and infrequent, you still get the metabolic benefits without derailing your muscle recovery and growth.
6 Listen to Your Body
At the end of the day, everyone’s body responds differently to cardio. Some guys can handle more, while others need to cut it way back to keep muscle gains coming. If you notice that your lifts are stalling, you’re not gaining weight, or you feel fatigued all the time, it might be time to dial back the cardio a bit.
The Fix: Pay attention to how your body feels. If your recovery is slow, your appetite drops, or you’re struggling to gain weight, reduce your cardio for a few weeks and see if your progress improves.
Why it works: Too much cardio can interfere with muscle recovery, appetite, and even sleep—all of which are essential for muscle growth. By adjusting your cardio volume to match your body’s needs, you can stay lean and healthy without sabotaging your gains.
7 The Bottom Line: Cardio Won’t Kill Your Gains—If You Do It Right
As a skinny guy trying to build muscle, cardio can feel like walking a tightrope. You want to stay lean and fit, but you don’t want to sacrifice all the hard work you’re putting in at the gym. The key is to do just enough cardio to boost your overall health, improve recovery, and keep your conditioning on point—without burning through the calories and muscle you’re working so hard to gain.
Stick to low-intensity cardio, time it wisely, and make sure you’re eating enough to support both your lifting and your cardio efforts. With the right approach, you can stay lean, keep your heart healthy, and still pack on muscle.
How do you balance cardio with building muscle? Share your strategy in the comments and subscribe for more no-BS fitness tips!
