DOMS - the science

🧬 What is DOMS?

DOMS refers to the muscle soreness and stiffness you feel 24–72 hours after unfamiliar or intense exercise, especially if it involves eccentric contractions (e.g., lowering a weight, downhill running).

It’s not caused by lactic acid, as was once believed. Instead, it’s linked to microscopic muscle damage and inflammation.

🧪 The Science Behind It

1. Microscopic Muscle Damage

DOMS is mainly associated with eccentric contractions (lengthening of muscle under tension).

These movements cause microtears in the muscle fibers, particularly the Z-discs of sarcomeres (the contractile units of muscle).

2. Inflammatory Response

Damaged muscle tissue triggers an inflammatory cascade:
 

Neutrophils and macrophages are recruited to clean up cellular debris.These immune cells release cytokines (like IL-6, TNF-α), which sensitize nociceptors (pain receptors).This leads to soreness, swelling, and reduced range of motion.

3. Calcium Leakage & Oxidative Stress

Disrupted muscle membranes leak calcium into the cell, activating enzymes like calpains that break down muscle proteins.This, combined with oxidative stress, worsens damage and prolongs the soreness.

⏱️ Timeline of DOMS

Time Post-Exercise

What’s Happening

0–12 hrs

Little to no soreness yet

12–24 hrs

Inflammatory markers increase

24–72 hrs

Peak soreness, stiffness, weakness

3–7 days

Recovery and adaptation occur

 

💪 Does DOMS Mean Growth?

Not directly. Muscle soreness is not a reliable indicator of a good workout or hypertrophy. You can:

Grow muscles without feeling sore.

Feel sore without achieving hypertrophy.

However, some level of tissue damage (and subsequent repair) is part of the adaptive process that builds muscle, but more isn’t always better.

🧊 DOMS Management

✅ What Helps:

Active recovery (light cardio, mobility work)

Massage or foam rollingSleep & proper nutrition (especially protein and anti-inflammatory foods)NSAIDs (in moderation) – can reduce pain, but may blunt muscle adaptation if overusedCompression garments

🚫 What Doesn’t Help (Much):

Ice baths (reduce pain but may also reduce hypertrophy)

Overtraining through the pain (can worsen recovery)Excessive stretching (might feel good temporarily, but doesn’t speed healing)

🧠 Adaptation & the Repeated Bout Effect

After you do a novel or intense workout, the next time you do the same thing, DOMS will be significantly reduced.

This is due to:

Neural adaptations (better motor control)

Structural remodeling (stronger connective tissue)Protective proteins (like heat shock proteins) increasing

This is known as the Repeated Bout Effect (RBE).

🔬 Summary

DOMS is a symptom of muscle adaptation, not a goal.

It results from eccentric overload, inflammation, and microscopic damage.While unpleasant, it’s a normal part of training, especially when starting something new.DOMS lessens over time due to neuromuscular adaptation.