Day 3 of 100 Days Muscle Resistance Workout Challenge
Topic: The role of muscle in burning calories, regulating blood sugar, and preventing metabolic disease.
Learning Material
Muscles aren’t just about movement—they’re one of the most important regulators of your metabolism. Think of them as both the engine that burns fuel and the sponge that soaks up sugar from your bloodstream. Without enough muscle, the body’s energy system runs less efficiently, increasing the risk of weight gain, diabetes, and metabolic disease.
Muscle and Calorie Burning
Muscle tissue burns calories even when you’re sitting still. The more muscle you have, the more energy your body uses to simply stay alive. While a single pound of muscle won’t dramatically boost your metabolism on its own, over time, building and maintaining lean mass helps keep your daily calorie burn steady—making it easier to manage weight.
Muscle and Blood Sugar Control
Muscles are the largest site in the body for glucose uptake. Every time you contract a muscle—whether lifting weights or going for a brisk walk—it helps shuttle sugar out of the bloodstream and into muscle cells for storage or use. A Japanese cohort study of young and middle-aged women found that lower relative skeletal muscle mass was strongly associated with reduced insulin sensitivity and impaired glucose tolerance, even among participants who were neither overweight nor diabetic1. This is why strength training and cardio are powerful tools for preventing type 2 diabetes.
Muscle and Metabolic Health
When muscle mass is low, the body becomes less sensitive to insulin, leading to higher blood sugar and increased fat storage. This can trigger a cascade of health problems, including obesity, diabetes, and heart disease. In contrast, keeping muscles active makes them act like a “shield” against these conditions.
Example / Story
Imagine two people who eat the same meal: one has strong, active muscles, while the other has very little muscle. The first person’s muscles quickly absorb the glucose, keeping blood sugar stable. The second person’s body struggles, leaving sugar in the blood, which eventually gets stored as fat. Same meal, completely different outcomes—all because of muscle.
My Reflection
At first, I thought I hadn’t pushed myself hard enough on Day 1 since I didn’t feel sore right away. But this morning, I woke up with aches in my legs and glutes—clear proof that the exercises were working after all.
When I checked my body composition, I noticed something surprising: my muscle mass is in the “dark green” range, which is high for my age. The real issue isn’t muscle but fat—most of my body fat comes from subcutaneous fat, while my visceral fat is less of a concern.
This shows me I need a balanced strategy: keep strengthening my muscles, while also adding more cardio and adjusting my diet to manage fat more effectively.
Today, I made a small but intentional change by starting breakfast with two eggs and a salad. I know this will support fat loss and help me feel satisfied. Still, I realize I’m not eating enough protein overall, so I’ll need to pay closer attention to my intake. After breakfast, I added some light leg stretches—another small step to keep my body moving and recovering.
Biometric data
Change in Weight from Day 1: 0lb
Skeletal Muscle: 38.8%
Muscle Mass: 95 lb.
Adjustment Ideas
- Add a short cardio session (e.g., 15–20 minutes of cycling, brisk walking, or jogging) 3–4 times a week to pair with muscle training.
- Reduce added sugars or refined carbs in one daily meal to help keep blood sugar stable.
- Incorporate more protein + fiber into snacks to feel full longer and support muscle repair.
Notes
- Hyeon-Ju Kwon et al., “Skeletal Muscle Mass Is Associated with Insulin Sensitivity and Glucose Tolerance in Japanese Women,” Diabetes Research and Clinical Practice 88, no. 2 (2010): 161–168, https://doi.org/10.1016/j.diabres.2010.02.010 ↩︎
Bibliography
Kwon, Hyeon-Ju, Kiyoshi Sanada, Motoyuki Midorikawa, Takashi Iemitsu, Kazushige Murakami, and Mitsuru Higuchi. “Skeletal Muscle Mass Is Associated with Insulin Sensitivity and Glucose Tolerance in Japanese Women.” Diabetes Research and Clinical Practice 88, no. 2 (2010): 161–168. https://doi.org/10.1016/j.diabres.2010.02.010.