The anaerobic threshold (AT), the point at which lactic acid starts to accumulates in the muscles, is considered to be somewhere between 85% and 90% of your maximum heart rate (HRmax) .
Ultimately, Windows Defender might fail to update the definitions itself for whatever reason. In such cases you must either force a definition update by navigating to the designated tab of Windows Defender or by downloading and installing the latest signature definitions. The Windows Defender Definition Updates are offline packages containing the most recent antivirus signature for Windows Defender. Once installed, they will make sure your PC is safe from the latest known viruses, spyware, PUPs, and malicious files.
Windows Defender is the default real-time (always on) protection program in Windows 8, 8.1 and 10. Unlike the one in Windows XP, Vista and 7, the Windows 8/8.1/10 version does protect from viruses and other types of malware, not only spyware.indows Defender uses Windows Update to download and install new virus and spyware definitions once a day. If updates fail constantly, follow instructions in the Reinstall Windows Update article. Please note that you cannot install Microsoft Security Essentials in Windows 8, 8.1 or 10.