Emfit QS is a sleep monitor. It is designed and manufactured in Finland. It consists of a thin, film-like sensor and a small control unit. The sensor is put under the mattress which is contact free and people can sleep usual. The sensor can detect people’s vitals during sleeping. The data includes heart rate variability, recovery, stress level, sleep stage classification, heart rate, respiratory rate, overall sleep score, movement activity and so forth. Research links high heart-rate-variability to good health and an optimal level of fitness, while decreased HRV is linked to stress, fatigue and even burnout. Tracking Heart-Rate-Variability throughout the night will give you a detailed picture of progression of your recovery during the night. The Evening RMSSD value shows accumulated stress over the day, and Morning RMSSD provides recovery status and readiness for a new day.