Have you ever experienced a string of lackluster workouts, only to follow them with sessions where you feel like a champion? If so, you’re not alone. According to the ‘rule of thirds,’ this fluctuation in workout quality is perfectly normal. However, if all your sessions start to feel boring or too easy, it might be time to reassess your fitness routine.
Understanding the Rule of Thirds
The ‘rule of thirds,’ popularized by Olympic runner Alexi Pappas, suggests that during your fitness journey—whether you’re going from Couch to 5K, training for your first marathon, or preparing for a Hyrox event—your progress won’t necessarily be linear.
“When I struggled with my splits before the Rio Olympics, my coach reassured me that it was okay—it was just the rule of thirds,” Pappas shared on the Rich Roll podcast. “He explained that while chasing a dream, you should expect to feel good one-third of the time, okay one-third of the time, and not so great the remaining third. If you find this balance, you’re on the right track.”
“This rule is a simple yet effective way to gauge whether your training is yielding results,” states personal trainer Aimee Victoria Long. “It signals that you’re challenging your body enough to promote growth while still allowing for necessary recovery.”
Applying the Rule of Thirds
This concept is particularly useful for assessing your training’s effectiveness and recovery. “If too many sessions feel hard, it could indicate accumulated fatigue or inadequate recovery,” explains Long. “On the other hand, if most workouts feel good, it may suggest that your intensity needs an adjustment to foster meaningful change.”
It’s important to note that achieving a good fitness level doesn’t mean every workout should feel easy. “Real progress often comes from moments of discomfort,” Long adds. “Those tougher sessions, where you push yourself, are typically the ones from which your body learns and develops the most.”
Things to Keep in Mind
As with any training principle, there are some nuances to remember. “It’s not so much about keeping perfect ratios or forcing hard workouts,” advises Long. “This pattern should naturally emerge when training is structured effectively. A challenging workout should feel demanding yet never result in pain or injury; rather, it should evoke a sense of focus.”
Additionally, recovery sessions should feel effortless. For newcomers to fitness, you might find that many workouts feel positive as you start your journey.
Final Thoughts
Once you’ve established a routine, particularly in areas like strength or endurance training, this rhythm of the rule of thirds commonly surfaces,” says Long. “Ultimately, this mindset helps you maintain perspective. It alleviates the pressure to have every workout be extraordinary while promoting honesty in evaluating your effort levels. The focus is on achieving balance, not perfection.”
Emma Barnett, a Radio 4 presenter, transformed her relationship with fitness through training with PT Frankie Holah after years of battling endometriosis and undergoing IVF. For Frankie’s complete training plan, download the Women’s Health UK app.
Hannah Bradfield is a Senior Health and Fitness Writer for Women’s Health UK. An NCTJ-accredited journalist, Hannah graduated from Loughborough University with a BA in English and Sport Science and an MA in Media and Cultural Analysis. She has been covering sports, health and fitness for the past five years and has created content for outlets including BBC Sport, BBC Sounds, Runner’s World and Stylist. She enjoys interviewing individuals in the community to improve access to sport, exercise, and wellness. A keen runner, she has shifted from sprinting to longer distance runs, enjoying the 10K distance most while also volunteering at parkrun every Saturday, followed by some well-deserved pastries. Hannah is always on the lookout for new running adventures and brunch spots.
