HIIT Exercise: High Intensity Interval Training

The Explosive Power of Movement

Your body was engineered for motion. Not casual, distracted motion, but purposeful, pulse-raising, oxygen-flooding movement. “In Him we live, and move, and have our being” (Acts 17:28). Movement is not optional; it is biological obedience.

Physical activity keeps the “living machinery” in harmonious action, but inactivity breeds congestion, weakness, and disease. Remember that circulation is life, and when blood moves efficiently, healing accelerates.

Now let’s go deeper into exercise, especially into High-Intensity Interval Training (HIIT), short bursts of intense effort (30 Sec to 60 Sec followed by a short recovery. Have you ever been chased by a dog? What do you do when you see that dog? Your heart starts racing, and the Fight or Flight response kicks in. You run as if your life depended on it. About a minute later, you look back, you see that you lost that dog, and you take a breather. About 30 seconds later, you hear a growling. You look back, it's that dog again. Before you know it, your body explodes into action, and you are running for your life again. After another 60 seconds, you look back, and the dog stops and seems to have lost interest in a fast gazelle like you. You breathe deeply, you are thankful, you go home and rest, and think about your ordeal and your near brush with death. This is the visual I give in my health seminars so that people can understand what this type of exercise looks like. It's not the long 30-60 minute exercise where you are doing the same thing. It's a variety of short, quick bust exercises, followed by short rest. When wisely practiced, HIIT exercises act like a biochemical wildfire, burning fat, rebuilding cells, and shocking the body into resilience. Understand that this type of training is not for everyone and that there are different levels of intensity training.

NOTE: If you are sick, talk to a health professional in this area who can safely advise you on the best exercise for you. Apart from going on a walk, exercises like HIIT are best when done before you eat, not after. This is not to say you can't eat before your workout, but if you do, to prevent digestive discomfort, give yourself at least 2 hours for simple meals and 3-3.5 hours for complex meals with meat. High-fat and high-fiber foods, eaten close to your workout, may cause indigestion and stomach cramps.

Here’s how exercise, particularly HIIT, impacts each major organ system:

🫀 Heart

HIIT strengthens the heart muscle like resistance training strengthens biceps. It increases "stroke" volume (how much blood the heart pumps per beat), lowers resting heart rate, and improves blood pressure. Short bursts of intensity train the heart to become more efficient, not just stronger. A powerful heart means greater endurance, lower cardiovascular risk, and sharper mental clarity.

🫁 Lungs

During HIIT, oxygen demand skyrockets. The lungs expand capacity and improve oxygen exchange efficiency. Over time, breathlessness decreases, and oxygen delivery improves. Deep respiration also helps eliminate carbon dioxide waste more effectively.

🧠 Brain

Intense exercise stimulates brain-derived neurotrophic factor (BDNF), often called “miracle grow” for the brain. HIIT enhances memory, mood, and neuroplasticity, "the capacity for the brain rewire and reorganize itself to adapt and function in new ways". HIIT reduces stress hormones like cortisol and increases endorphins and dopamine, natural antidepressants.

🩸 Blood & Circulation

HIIT improves insulin sensitivity dramatically. Glucose gets shuttled into muscle cells more efficiently, reducing blood sugar spikes. Red blood cell production improves oxygen transport. Arteries become more elastic, reducing cardiovascular strain.

🦴 Bones

Weight-bearing intervals stimulate osteoblast activity (bone-building cells). This strengthens bone density and helps prevent osteoporosis. Jumping, sprinting, and resistance intervals send mechanical signals that bones must grow stronger.

💪 Muscles

HIIT recruits both slow-twitch and fast-twitch fibers. Fast-twitch fibers, responsible for power and explosiveness, decline with age unless stimulated. HIIT preserves youthfulness in muscle composition while increasing mitochondrial density (your cellular energy factories).

🧬 Metabolism & Hormones

Short bursts of intensity elevate human growth hormone (HGH) and improve testosterone balance (in both men and women). Metabolic rate increases not only during exercise but for hours afterward (EPOC—excess post-exercise oxygen consumption). This means your body continues burning calories long after the workout ends.

🧽 Lymphatic System

Unlike blood, lymph has no pump. It moves through muscle contraction. HIIT acts like a detox engine, pushing lymph fluid through channels, helping remove cellular waste, and supporting immune strength.

🛡 Immune System

Moderate HIIT strengthens the immune response by improving circulation and reducing chronic inflammation. However, balance is crucial; overtraining weakens immunity. Temperance still applies.

Biblical & Spiritual Dimension

The Bible repeatedly links physical vitality with spiritual clarity. Daniel’s disciplined lifestyle enhanced his wisdom (Daniel 1:20). Paul compares spiritual endurance to athletic discipline (1 Corinthians 9:24–27).

Exercise is not vanity; it is stewardship.

But intensity must be balanced with recovery and avoid extremes. Overexertion without rest can raise cortisol levels excessively. Even HIIT should be limited to 2–4 sessions per week, with walking and restorative movement on other days.

Practical HIIT Example (Beginner-Friendly)

• 30 seconds brisk sprint or fast cycling
• 60–90 seconds slow recovery
• Repeat 6–8 times
• Total time: 15–20 minutes

Always warm up and cool down.

⚡ Call to Action

This week, schedule two short HIIT sessions. No excuses. No procrastination. Ignite your heart. Flood your brain. Cleanse your bloodstream. Strengthen your bones.

Your body is divine machinery. It was designed to roar, not rust. So get up and get MOVING!

HIGH

INTENSITY

INTERVAL

TRAINING