The Latest On Resistance Training

This week in the world of sports science, resistance training, Rodri, Harry Kane, and ChatGPT.

Eric Curry

By Eric Curry
Last updated: March 25th, 2026
4 min read

This week in the world of sports science, here’s what happened…

  • The latest research on resistance training
  • The inspiring journey of Rodri and Harry Kane: from rejection to stardom
  • Is ChatGPT more reliable than personal trainers?

The latest research on resistance training

(Image: Science for Sport)

In 2009, the American College of Sports Medicine (ACSM) released one of the most impactful papers on resistance training, which has been cited nearly 4,000 times (see paper here). Now, 17 years later, the ACSM has published an updated version of this paper (see here). Senior Exercise Science Lecturer Dr Jackson Fyfe has summarised the key findings of this update in a recent social media post.

Interestingly, as Fyfe notes, this update isn’t so much about what has changed, but rather what we’ve realised doesn’t matter as much as we once thought. For instance, the paper emphasises that most resistance training programs are effective if participation and consistency are maintained. Variables such as periodisation, training to failure, time under tension, and the debate between machines and free weights may not be as critical as we previously believed. The main takeaway from Fyfe’s insights is that focusing on “training with effort, achieving sufficient total work, and progressing slowly over time” are the most significant factors in resistance training.

When it comes to building strength, the updated ACSM guidelines suggest training with heavier loads at least twice a week and utilising a full range of motion. For those aiming for hypertrophy, the emphasis is on volume as the key variable. While various methods can promote muscle growth—such as training to failure or using different weights—volume remains the most vital aspect.

In summary, the primary message from this new update is that the real challenge with resistance training lies in participation, not effectiveness. To dive deeper into the details of the update, checking out Fyfe’s social media post is certainly recommended.

The inspiring journey of Rodri and Harry Kane: from rejection to stardom

Rodri (Image: BBC)
Harry Kane (Image: The Telegraph)

Last week, Dr Juan Delgado shared a thought-provoking infographic on LinkedIn showcasing the journeys of prominent football stars Rodri and Harry Kane (check out our SFS Weekly edition “The Secret To Harry Kane’s Success!” for information on Kane’s story). Interestingly, Rodri was released from the Atlético Madrid youth academy in 2013 for lacking physical strength, while  Kane was let go by the Arsenal F.C. youth academy at just eight years old for being “too chubby.” Both players defied the odds, and fast forward to today, Rodri is a Ballon d’Or winner, and Kane has become England’s all-time top scorer.

Delgado’s infographic also emphasises that youth players of the same chronological age can have up to a six-year biological age gap. Scouts often focus primarily on attributes like speed, strength, size, and physicality, leading them to overlook late bloomers like Rodri and Kane. Consequently, vital aspects like football intelligence, tactical awareness, and psychological qualities such as resilience and leadership are frequently overlooked.

While the remarkable career paths of Rodri and Kane serve as inspiration, Delgado’s infographic effectively underscores the importance of understanding maturation when working with young athletes. If you’re interested in learning more about maturation, our detailed course How does age and maturation affect motor coordination and performance? It is well worth checking out.

Is ChatGPT more reliable than personal trainers?

(Image: Mint)

A recent study has raised some concerning findings for personal trainers! In this study, nine active personal trainers submitted their most frequently asked questions along with their responses. These questions were then posed to ChatGPT, and a panel of topic experts compared the answers from both the personal trainers and ChatGPT.

The experts evaluated the responses based on scientific accuracy and found that ChatGPT outperformed the personal trainers for most questions. While this research suggests that ChatGPT can serve as a reliable resource for commonly asked exercise training questions, it also underscores a troubling reality: the level of knowledge and the ability to provide scientifically sound answers among personal trainers is questionable. If this gap isn’t addressed, there’s a real risk that some personal trainers could be replaced by chatbots!

From us this week:

>> New course: Performance Analysis in International Football
>> New podcast: The Role of Environment in Player Performance
>> New infographic: Hydrotherapy
>> New article: Hydrotherapy

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Eric Curry

Eric Curry

Eric is a Strength and Conditioning Coach from Ireland. Eric holds a MSc in Sports Strength and Conditioning and an undergraduate degree in Sport and Exercise. Eric is also a Certified Strength and Conditioning Specialist (CSCS) with the NSCA. Eric currently works as a Strength and Conditioning Coach in Ireland predominantly with youth performance Tennis players. Eric also has experience working with athletes from basketball, martial arts, football, hurling, and Gaelic football.

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