I'm 13 (near 14) and I am a forward in rugby. I want to bulk up to improve my performance but I dont want to get fat. I run regularly to improve my cardio and I obviously have that right because I have a low heart rate at rest (around 55bpm). I used to do a mainly cardio workout (insanity) and it would leave me with sore muscles (growing obviously). I decided about a week ago to start working on specific muscle groups instead. I have two 5kg dumbbells and I am lifting them in different exercises. My muscles shake and feel worked but after 3 minutes or so the aches are gone permanently. I am confused because whenever I did Insanity my muscles were aching when I got out of bed the next morning. Am I not doing something right? I do a 10min ab workout once a day and it leaves my abs feeling sore like insanity did. Please could I have your suggestions of what I should do better, more of, differently... etc.
Ty =D
Ty =D