Hardgainer over 40 looking for advice to finally put on some muscle

[pettersson]

You provide enough background details to motivate a response. Take my suggestions for what they are.

Being a hardgainer you have already realized the importance of proper diet (need for additional calories). Compound excercises are never wrong, but considering your knee problem you need an alternative route, at least for the time being. You also mention “time under tension” which I interpret you being open minded in terms of ways to train.

I would advise you to obtain proper knee sleeves, if you already haven’t - which makes all the difference!

Also, make sure to always do a 5-10 min dynamic bodyweight warmup for lower and upper body! In your case a less resistance bike warmup may be the only thing you can do for lower body?

As for supplements, I have positive experiences with omega-3 and collagen type 2 supplementation combined for joint symtoms.

The knee injury forces you to lower the weights being used, and establish proper movement control. This is where HIT (according to Dr Darden) comes to mind. Full body workouts, 2-3 times a week, one-two sets per bodypart, 8-12 excercises per workout. And maybe most important the focus on negatively emphasized training AND not til failure (at least one rep in reserve) - partly as a rehab tool, but also to make most use of the low volume training.

I highly recommend you carefully shock your system with Dr Darden’s 30-10-30 routine, or if not comfortable with timing your sets - the regular 4 sec pos / 4 sec neg tempo approach for 10 reps/set.

Growth Explosion: The 30-10-30 Technique

[Growth-Explosion-The-30-10-30-Technique] A Once-a-Week Workout Plan for Fast Gains Three young athletes gained 14 pounds in 14 days using a new training technique. Here’s exactly how they did it. 14 DAYS, 14 POUNDS Using primarily negative (eccentric) exercise, Jordan Rapport, age 17, gained an average of one pound of muscle a day for 14 consecutive days. Jordan was involved in my supervised, six-week, Intensive Coaching program. A typical bodybuilder would be pleased to add 14 pounds of…

Check this link for further info on the 30-10-30 technique. Skip the sensational parts, even though it may be true to some extent. You may use it for also lowering your training frequence - how about twice weekly, which I myself have successfully deployed for the past 4 years with great outcomes?

One final thought: There seems to be scientific evidence for training only one side of the body (leg) when suffering from injury - and still maintain decent status on your weak limb. This may mean you can do heavy one legged movements with your fresh leg, and low weight (rehab) movements with your injured leg (to preserve function). I would definitely consider this in conjunction with the 30-10-30 approach.

Best of luck!