Disclaimer

Not medical advice

The exercises, tools, and articles on this site are provided for general wellness, education, and entertainment purposes only. They are not medical devices and are not intended to diagnose, treat, cure, or prevent any eye condition, vision impairment, cognitive condition, or other medical condition. Scores such as reaction times or memory levels are informal personal benchmarks, not clinical assessments. Nothing on this site constitutes professional medical advice.

Consult a professional

If you have an existing eye condition, vision problem, or any concerns about your eyesight, please consult an optometrist, ophthalmologist, or other qualified healthcare provider before using the eye exercises. If you have a heart, lung, joint, or other medical condition, are pregnant, take medication, or have been inactive for a while, talk to a doctor before starting a new exercise program — including running, interval training, or weight training. For changes to your diet, a registered dietitian can give advice tailored to you.

Articles

Articles on this site summarize published scientific research for a general audience. They are written for education and general interest and are not a substitute for advice from a doctor, eye-care professional, psychologist, registered dietitian, qualified exercise professional, or other qualified provider. Research findings can be limited, disputed, or overturned by newer studies, and an article may not reflect the most current evidence. Where articles describe medical conditions, clinical therapies, or study results — for example, research on dementia, anxiety, vision therapy, diet, or weight loss — these are descriptions of research, not recommendations for diagnosis or treatment. Never disregard professional advice or delay seeking it because of something you read on this site.

Calculators

The calculators on this site use standard published formulas to produce general estimates for healthy adults. Individual needs vary. BMI does not account for factors such as muscle mass, age, or body composition, and the U.S. Navy body fat method is a tape-measure estimate that can differ from laboratory measurements by several percentage points. Results are not dietary or medical advice — talk to a doctor or registered dietitian before making significant changes to your diet, weight, or exercise routine, especially if you are pregnant or breastfeeding, have a medical condition, or take medication.

The weight loss timeline calculator is an estimate based on a simplified energy model; real weight change differs from it. Rapid weight loss and very-low-calorie diets carry health risks and should only be undertaken with medical supervision. These calculators are not intended for children or for anyone with a history of disordered eating.

Heart rate zones are based on estimated maximum heart rate, which can be off by 10 bpm or more for an individual and is affected by medication such as beta blockers. Consult a doctor before beginning vigorous exercise, particularly if you have a heart condition, high blood pressure, or have been inactive. The barbell plate calculator only performs arithmetic — lift within your ability, use collars and safeties, and stop if you feel pain.

Breathing exercises

The breathing exercise involves slow breathing and short breath holds. Breathe gently and never force a hold. If you feel dizzy, lightheaded, short of breath, or unwell, stop and return to normal breathing. Do not practice while driving, operating machinery, in water, or in any situation where losing focus could be dangerous. If you are pregnant or have a heart, lung, or other medical condition, consult a healthcare provider before trying breath-holding techniques. The exercise is not a treatment for anxiety, panic, sleep problems, or any other condition.

Photosensitivity warning

Some exercises involve moving, flashing, or rapidly appearing and disappearing visual elements — including full-screen color changes in the reaction time tests and brief color flashes in Mental Math Practice. If you or anyone using this site has photosensitive epilepsy or a history of seizures triggered by flashing lights or patterns, please use caution, keep exercise speeds low, or avoid this site entirely. Stop immediately if you experience dizziness, eye strain, headache, or discomfort. The audio reaction test plays a beep, so set a comfortable volume before starting, especially when using headphones.

Use at your own risk

You use the exercises and calculators, and act on information in the articles, entirely at your own risk. This project is provided “as is,” without warranties of any kind, express or implied, including but not limited to fitness for a particular purpose. The site owner is not liable for any injury, discomfort, or damages arising from use of this site.