Problem with drain battery

I record the track as always. Hike. Standard settings. Bicycle. Same. For about a month locus has been drain battery of the phone at an express pace. The phone in airplane mode without the network is enough for 8 hours max. Previously, it was about 14 to 16 hours of recording alone. Can someone tell me what is the reason for this? Once, over a year ago, it was the same for a long period of time, but after the updates the problem disappeared.