Episode 177-Sharkbanz/Adam Barker

A brief synopsis of the episode's main discussions and takeaways as well as extended references

Author

Jeff Sankoff
August 15, 2025

I am off in Bonaire SCUBA diving this week but the supplement comes to you all the same. Should I have taken a shark deterrent with me for my time swimming in the open water? Read on to see what we found about the tech involved in magnetic bracelets and disorienting Jaws. Also, my interview with extreme sport photographer, high level amateur cyclist and now entrepreneur, Adam Barker.

Table of Contents

Sharkbanz and other shark deterrents Should we consider these products as a means to decrease the likelihood of shark bites?

Exploring the intersection of nutrition and athletic performance, the podcast begins with an engaging discussion about quercetin, a natural flavonoid known for its potential health benefits. The hosts delve into the claims surrounding quercetin's ability to prevent respiratory illnesses, particularly during the cold and flu season. They scrutinize various studies, highlighting how quercetin may inhibit viral entry into cells and its implications for endurance athletes, who often face a dip in immune function after intense training sessions. The conversation emphasizes the importance of realistic goal-setting for athletes and how supplementation can play a role in achieving those goals without compromising health. The hosts wrap up this segment by inviting listeners to consider how they might incorporate quercetin into their training regimens, all while maintaining a light and relatable tone that encourages personal experimentation and discussion within the community. This segment is peppered with practical advice, encouraging athletes to consider how supplements like quercetin might fit into their overall training strategy while emphasizing the need for achievable goals that push personal limits without risking health.

Adam Barker-Award winning photographer, cyclist and entrepreneur

Adam Barker is an Utah‑based commercial and adventure photographer raised in the scenic Wasatch Mountains of Utah. His work spans editorial, advertising, and lifestyle photography, frequently appearing in publications like Men’s Journal, Outdoor Photographer, Powder, Flyfish Journal, and USA Today. In 2024, Adam decided to pivot into entrepreneurship. The catalyst? A personal need: as an avid cyclist shaving his legs since 2008, he was frustrated by the lack of products designed for men who shave their legs.

Barker’s X Games Award-winning photo

In a world where every man is trying to figure out how to stay aerodynamic while cycling, Adam Barker has cracked the code. Forget the old pink razors and awkward bathroom moments; Adam has created a shaving system that caters to the rugged needs of male athletes. As a photographer, Adam's lens has captured the thrill of extreme sports, and now he’s turning that same passion into a thriving business that helps men embrace their smoothness without the embarrassment.

We kicked off our discussion with Adam sharing his journey from an award-winning photographer to launching his own brand, Bolt Shaving. It’s a tale filled with daring escapades, from shooting in the Wasatch Mountains to navigating the chaotic world of entrepreneurship. Adam recounts his experiences at various expos, where he brings his product to life and interacts with fellow athletes who are just as passionate about cycling and triathlons as he is.

Adam gets real about the challenges he faced in the startup landscape, discussing everything from funding to marketing. He humorously highlights the absurdity of trying to convince folks that shaving isn’t just for women, and that maintaining leg hair might actually slow you down in a race. His perspective is refreshing and filled with genuine passion, making it clear that his journey is about more than just business success; it’s about changing perceptions and encouraging men to embrace self-care in a world that often mocks it. So, if you're into sports, photography, or just love a good story about defying the odds, tune in and get ready for some laughs and insights into the world of male grooming.

Episode takeaways:

  • Shark deterrents, or as I like to call them, 'the latest gimmick for fearful swimmers,' are hilariously ineffective, proving that just because something sounds cool doesn’t mean it works—because who doesn’t want to swim with sharks?

  • We discuss the behind-the-scenes grind of professional photography, from scouting locations to capturing that perfect shot, and how it all sounds glamorous until you realize it’s a lot of waiting around in freezing conditions.

References used for the MMB

Huveneers, C., Whitmarsh, S., Thiele, M., Meyer, L., Fox, A., & Bradshaw, C. J. A. (2018). Effectiveness of five personal shark-bite deterrents for surfers. PeerJ, 6, e5554. https://doi.org/10.7717/peerj.5554

  • Created a surfboard set up, lured in sharks with tuna bait, added some deterrent (this study tested 5 deterrents, most surf-specific like board wax, but including Sharkbanz), analyzed shark behavior. (Focused on surfing, not swimming, still somewhat relevant!)

  • Magnetic (like Sharkbanz) and olfactory deterrents (e.g., Chillax Wax) showed no measurable behavioral impact at personal-use scales (≤0.5 m range).

    • This has to do with the magnets of Sharkbanz generating a magnetic flux that decays with distance, becoming basically negligible by 0.3-0.5 meters. 

    • An argument the authors make for the validity of Sharkbanz, despite its inefficacy: at the magnetic source, as opposed to at some distance from the magnet, there is evidence that magnets do deter a variety of shark species. Also, other research has confirmed that the threshold at which the receptors responsible for electroreception in sharks detect electricity is much lower than these types of magnets.

This article was negative enough about the real-world efficacy of Sharkbanz that it prompted a reply from Sharkbanz co-founder Nathan Garrison, reported on by Forbes: 

  • Garrison’s response: the study was flawed because the bait used was too appealing. A real usage-case of Sharkbanz is a person (not some tuna gill), which a shark would just need mild dissuading from.

  • Sharkbanz says the goal is deterrence and risk reduction, not elimination of risk, but that that is worth having.

  • The thought behind Sharkbanz is that creating a magnetic field (especially in saltwater) will confuse/disorient a shark, which is able to sense the world via electroreception/magnetoreception.

  • Proof of principle: early studies showed that sequentially placed magnets could alter shark swim paths. Most research is done on bull sharks or great white sharks. 

  • Sharkbanz-sponsored study showed experimental evidence (that was reviewed by third-party independent group, but should still be taken with a grain of salt as it was designed and sponsored by Sharkbanz and not peer-reviewed in the scientific community) that Sharkbanz was effective at repelling sharks in a simulated bait-exacerbated high risk situation: https://cdn.shopify.com/s/files/1/1826/7677/files/Sharkbanz-Bull-Shark-Response-Research-Paper-June-2018-Comp.pdf?v=1661295573. 

    • Their finding: significantly fewer shark bites in Sharkbanz treatment condition compared to control.

O’Connell, C. P., Crews, J., King, A., & Gressle, J. (2022). Evaluating the Shark Deterrent Effects of the Novel Exclusion Barrier in Comparison to the Rigorously Tested Sharksafe Barrier Technology. Journal of Marine Science and Engineering, 10(5), 634. https://doi.org/10.3390/jmse10050634

  • Magnets can alter shark swim paths even in baited sites, meaning that sequentially placed magnets can be used to “shark-proof” an area - perhaps relevant for competition environments, less so for personal use. This is just an interesting tidbit.

Relevant excerpt from Huveneers et al. on the efficacy of Sharkbanz:

“Neither the SharkBanz bracelet nor leash affected the behaviour of white sharks or reduced the percentage of baits taken. These products rely on permanent magnets (Grade C8 barium ferrite; BaFe2O4), which have previously been used to overwhelm the electromagnetic sense of sharks. The voltages caused by the induction-based mechanism of the magnets substantially exceed the detection threshold of elasmobranchs (e.g., Jordan, Mandelman & Kajiura, 2011; Kajiura & Fitzgerald, 2009). Permanent magnets have also been shown to elicit avoidance in a range of species, including Galapagos (C. galapagensis), hammerhead (S. mokarran and S. lewini), lemon (Negaprion brevirostris), Australian blacktip (Carcharhinus tilstoni), grey reef (C. amblyrhynchos), bull (C. leucas), milk (Rhizoprionodon acutus), speartooth (Glyphis glyphis), and white sharks (O’Connell et al., 2018; O’Connell et al., 2014a; O’Connell et al., 2014b; O’Connell et al., 2015; O’Connell et al., 2011; O’Connell et al., 2010; Rigg et al., 2009; Robbins, Peddemors & Kennelly, 2011). However, the distance from which sharks reacted to magnets in those studies was small, typically <0.5 m (O’Connell et al., 2014a; Rigg et al., 2009) and the effectiveness of the magnets decreased with increasing shark motivation (Robbins, Peddemors & Kennelly, 2011). Barium-ferrite permanent magnets generate a flux that rapidly decreases in intensity, from ∼1,000 G near the magnet to an amount comparable to the Earth’s magnetic field (0.25–0.65 G) at distances of 0.30–0.50 m (O’Connell et al., 2014a; O’Connell et al., 2014b), showing how rapidly the magnetic field decreases. Sharks would therefore need to be <0.30 m for such magnets to act as real deterrents.

This suggests that magnets are unlikely to be effective at deterring sharks because they will only protect close to the magnet, limiting their applicability as personal deterrents unless stronger magnets can be used or many magnets are positioned on the surfer or board. The latter would add weight to the board and diminish its performance. However, several studies have shown the potential use of strong magnets in combination with visual deterrents to prevent sharks from entering some areas (e.g., beaches, embayments) (O’Connell et al., 2018; O’Connell et al., 2014b). Neodymium-iron-born (‘rare earth’) magnet is the strongest permanent magnet currently available and could be a more powerful deterrent than ferrite magnets. Rare earth magents have much higher surface field strengths than barium-ferrite magnets and might elicit avoidance response from further away (Rigg et al., 2009).”

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