Heart rate increase

Hey guys..i have had a new job since the end of march now and its a computer job and ive been doing alot of sitting down! And not walking as much as i used to..ive noticed that my heart rate is much higher now and i dont know if its to do with me not doing much exercise than i used to? My resting heart used to be 69 and now its gone up to 80 its worrying me to be honest :( i hope i am not losing my fitness! Any tips on how to keep your heart healthy? Just scared to be honest the last time it was that high was when i was not exercising and was over weight 😔

Also this new job is putting alot of pressure me too and i am always getting pushed and pushed its actually bringing me down

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