The New Year always inspires fresh aspirations of fitness success – more muscle, less fat, better endurance.
Unfortunately, many resolutioners go too hard out of the gate and injure themselves.
So instead of celebrating fitness success, active adults flood into my physical therapy clinic for rehab.
So without further ado, here are 5 principles to reduce injury risk and boost your odds of success in 2025.
1) SAID
SAID stands for specific adaptation to imposed demands. In other words, practice makes proficient. The human body adapts to perform the specific task it’s asked to do.
Also known as the specificity principle, this is an exercise science pillar and the foundation of every well-designed training plan.
For example, stretching improves flexibility. It won’t make you an elite runner.
Only running can do that.
Conversely, running won’t make you flexible. Adaptations are training-specific.
The best way to bike faster is to practice biking. And if you aim to squat a personal best, you need to practice squatting heavy weight.
However you define fitness success, the specificity principle simplifies exercise selection.
Here’s how adaptation occurs:
2) Stress – Recovery – Adaptation
Exercise puts stress on your muscles, joints and bones (in a good way). After adequate rest, your body recovers from the stress placed upon these structures. Then, adaptation occurs so your body can perform at a higher level next time.
Your body gets weaker at the gym. Training is all about applying stress.
You get stronger as you sleep, rest and relax. Prioritize recovery to maximize adaptations and progress faster.
3) Repeated Bout Effect
Have you ever run or lifted weights for the first time in a few months? Then you’re so sore that it takes heroic effort to climb the stairs or pull on a jacket?
The repeated bout effect explains this phenomenon. Novel and unfamiliar exercises cause delayed-onset muscle soreness.
But each “repeated bout” of performing the same exercise creates less soreness as your body adapts to the specific stress placed upon it.
Despite aching muscles after the first few training sessions, it will get better. Post-exercise soreness will subside as your body adapts to the new exercise.
During my powerlifting training, it’s normal for me to bench press >330 lbs, squat >500 lbs, and deadlift >600 lbs in the same week.
While it’s inaccurate to say I feel zero muscle soreness, it’s tolerable and doesn’t impact my day-to-day life.
It hasn’t always been this way. My body has built a tolerance to lifting heavy so “leg day” doesn’t cause can’t-stand-up-from-the-toilet soreness anymore.
On the other hand, I haven’t run sprints in years. So I’m about 4 wind sprints away from debilitating muscle soreness.
4) Progressive Overload
Progressive overload is the key to progress.
It’s a simple concept – gradually do more over time – but few people apply it to their training.
Because it’s more fun to implement complex training techniques like muscle confusion, super sets, drop sets and blood flow restriction.
But incrementally adding weight to the bar, increasing repetitions or running a bit faster is the simple path to progress.
5) Sleep
Sleep is underrated.
Stanford researchers found that extra sleep sharpens reaction time, boosts physical performance and enhances hand-eye coordination.
Sleeping less than 7 hours almost doubles injury risk. Suboptimal sleep also causes impaired focus and worse mood.
Not to mention sleep deprivation’s dreadful effects on weight loss, explained here:
Sleep for Weight Loss: The Emerging Connection
Training hard is important. So is rest and recovery. You won’t achieve peak physical and mental performance if you neglect sleep.
Further Reading
Is poor sleep keeping you from fitness success? Check out my huge sleep guide that’s chock full of evidence-based sleep strategies.
For more evidence-based health tips, join the free Facts & Physio Newsletter. Plus, get The Recovery Checklist e-book when you sign up.
Finally, if you need expert guidance to reach your 2025 health goals, you can apply here to work with me.
