How to Improve REM Sleep: What Women Should Know

A wearable sleep patch that uses ultrasound to influence brain activity has produced an intriguing early result: more rapid entry into rapid eye movement sleep and longer time spent in that stage. For women asking how to improve REM sleep, however, the findings are a prompt for careful investigation rather than a reason to reach for a new device.

Sleep technology is developing alongside broader attempts to make health research more biologically relevant. New patient-derived models of uterine tissue, for example, are intended to address limitations in animal research and improve how findings translate into gynecologic care. The connection matters. Whether researchers are studying a device, medication, supplement or training strategy, women-specific physiology cannot remain an afterthought.

How to improve REM sleep without overreading one study

REM sleep supports memory processing, learning and emotional regulation. It occurs in cycles across the night, with longer REM periods usually concentrated toward morning. Shortening sleep can therefore disproportionately remove REM-rich hours, even when total sleep loss appears modest.

In a study involving 28 participants, a wearable ultrasound patch reportedly reduced the time taken to enter REM sleep by 43 minutes and extended REM by roughly 16 minutes. Researchers also identified changes associated with emotion-related brain circuits and stress regulation. These are notable signals, but the sample was small, and a single experiment cannot establish durable benefits, safety across repeated use or meaningful effects on health and performance.

It is also important to separate changing a sleep-stage measurement from improving how someone functions. More REM is not automatically better in every context. The clinically relevant questions include whether a person feels more restored, maintains stable mood and attention, recovers well from training and experiences benefits without disrupted deep sleep or adverse effects. Independent replication in larger and more diverse groups is essential.

Female hormones can change sleep architecture

Women’s sleep is shaped by age, menstrual phase, pregnancy status, symptoms and hormone transitions. Progesterone and estradiol interact with temperature regulation, breathing, mood and sleep timing. Some women notice poorer sleep in the late luteal phase, particularly when premenstrual symptoms, pain or a rise in body temperature are prominent. The size and consistency of these changes vary substantially.

Perimenopause introduces another layer. Fluctuating hormones can coincide with night sweats, hot flushes, anxiety, altered cycle timing and nighttime waking. Menopause can also bring changes in body composition and sleep-disordered breathing risk. A technology that modifies neural activity may eventually prove useful, but it does not automatically address the cause of repeated waking, whether that is vasomotor symptoms, pain, insomnia, apnea, medication effects or an environment that is too warm.

The available summary of the ultrasound study does not establish whether outcomes differed by sex, menstrual phase, contraceptive use or menopausal status. Those omissions limit what can be concluded for women. A device intended to influence sleep should be tested across hormonal states, with adverse events, next-day cognition and longer-term sleep architecture assessed rather than inferred.

Training, nutrition and REM sleep are closely linked

Exercise generally supports sleep, but training load and timing matter. Regular aerobic activity and resistance training are associated with better sleep quality in many adults. By contrast, sudden increases in volume, late high-intensity sessions and inadequate recovery can delay sleep or increase nighttime waking in some people. The response depends on baseline fitness, schedule, temperature, nutrition and individual sensitivity to stimulation.

Low energy availability is especially relevant to active women. When dietary intake does not adequately cover exercise and basic physiological needs, consequences can include fatigue, impaired recovery, menstrual disruption, reduced bone health and poorer performance. Sleep disturbance can occur alongside these signs. A sleep device could potentially alter a nightly metric while leaving the underlying mismatch between training and fuel untouched.

Nutrition also affects sleep through several practical pathways. Caffeine can remain active for hours, while alcohol may make sleep onset feel easier but fragment the second half of the night and disrupt normal sleep architecture. Large meals close to bedtime may aggravate reflux or digestive discomfort. Conversely, persistent hunger after evening training may indicate that total energy or carbohydrate intake is insufficient.

No single food or supplement reliably increases REM sleep in a clinically useful way for everyone. Evidence for commonly marketed sleep ingredients is mixed, product quality varies and some supplements interact with medicines. The more informative approach is to examine timing and patterns: caffeine exposure, alcohol, evening meals, training load, cycle symptoms and the following morning’s energy.

Better models should produce better evidence for women

The same translational problem appears elsewhere in women’s health research. Opal Therapeutics is scaling a patient-derived gynecologic drug-screening platform described as a “uterus in a dish.” The aim is to create human-relevant preclinical models where rodent studies may not adequately represent uterine biology or predict treatment response.

This work is not directly about sleep or exercise. It does, however, illustrate the standard women should expect from emerging health interventions: models and clinical studies that reflect the tissues, hormones and life stages involved. A sleep technology tested without adequate female-specific analysis may miss differences in efficacy, tolerability or the reasons sleep is disrupted in the first place.

That principle applies equally to recovery products, nutrition protocols and wearables. Novelty is not a substitute for representative samples, appropriate control groups, transparent outcomes and enough follow-up to identify harms as well as benefits. Early findings can justify further study without justifying confident consumer claims.

Make recovery patterns readable over time

A single night’s REM estimate can be distorted by illness, alcohol, stress, travel, room temperature or a wearable’s measurement error. Consumer trackers estimate sleep stages indirectly and are generally less reliable than clinical polysomnography. Trends in total sleep, awakenings, morning energy and training recovery are often more useful than treating one REM percentage as a precise biological score.

Sleep quality, cycle symptoms, energy and training recovery only become readable when they are logged consistently over weeks. This is the kind of pattern Tulsy is built to surface.

Sources: ScienceDaily, FemTech Insider.

This content is for informational and educational purposes only. It is not intended to diagnose, treat, cure, or prevent any disease, and should not replace advice from a qualified healthcare professional.