a 58 year old neighbor approached me yesterday at the pool after i came back from my workout. he asked about my routine. he is a big guy (6'3, 252 lbs.) in great shape for his age. he definitely is a former heavy lifter, as he still has huge shoulders, arms, and legs. he is struggling recently because a knee injury has forced him to not lift any legs, which he claims was about 70% of his workouts now. talking to him reminded me of this thread.
if you lift long enough, you will be able to find ways your body best reacts to lifting. for instance, some studies show that running or doing cardio on a caloric deficit will reduce your muscle mass. however, i have seen that to be the most efficient way for me to take away that last bit of fat over the lower abs or other trouble spots when in a cutting phase. getting up early and doing even just a mile of high-intensity cardio before eating anything has worked wonders for me. the more you lift, the more you learn about how your body reacts to things and the best practice methods for you to accomplish certain goals.
as you mentioned, protein is very important. creatine also is, especially as guys get older. muscles dont recover as fast when you are older. creatine is a huge boost for that. i havent taken any supplements in 4-5 years, but if youre going to use protein, i highly recommend creatine, also. both protein and creatine supplements have been extensively researched for decades with neither of them being a danger to your body.
the reason i was against a smith machine is because of injuries and taking away the use of stabilizing muscles. as people get older, their balance becomes a major issue. taking away working the stabilizer muscles is a very bad idea. core exercises should be mandatory, as they help with balance. but, it sounds like you wont be getting one of those.
after you are comfortable lifting for a while, i highly recommend supersets for just about every body part. you can do a set of biceps, then immediately transition to a tricep lift. your biceps shouldnt be used in the tricep lift, so they wont be exhausted to the point of not being able to accomplish that tricep exercise. you can do the same things with legs (quads, hamstrings) and shoulders. you can also do three sets of biceps right after each other, working different parts of the biceps. doing this not only greatly reduces the time of your workouts, but gives you a hell of a cardio workout at the same time.
the best cardio i do is supersetting a number of lifts repeatedly.
being on the beach, i have gotten into a lot of bodyweight exercises. i run 4-5 miles to the busier areas of the beach where they have pull-up bars and other equipment. doing pull-ups/hanging arm flex really is a good break from using traditional weights.
if you want to avoid squats (which i disagree with carl about you not doing them), there are some really good bodyweight leg workouts that i do. the cardio benefit from doing them is amazing, and when finished, i struggle walking down stairs because my muscles are so exhausted. i can find some youtube videos of them if you want. i mix those with pilates exercises for legs, which make me sweat as much as anything i do.
to answer some of your questions . . .
i cant imagine that walking 5-10 miles per day would impact your lifting unless your body is really sore or exhausted from the walking. i know you enjoy that time with your wife, but i recommend some higher intensity cardio besides just that. you dont have to be sprinting, but getting your heart rate elevated more than what it is in a casual walk (assuming you guys arent power walking) is important.
if you dont care about impressing anyone with your appearance/strength and are more focused on general health, i think the supersets i mentioned earlier are a good idea. again, it gives you a needed cardio benefit while lifting. further, being a bit tired when you lift inhibits you from lifting your maximum amount of weight, so you wont be worried about bulking up or injuring yourself from lifting too heavy of weights.
i have a lot of free time, so my workout routine now is a bit longer than most people can do in a day. besides the walks with your wife, if you can set aside 45 minutes for lifting and more cardio, you will ahead of where you want to be, assuming you dont take long rests in between lifting sets.
day 1: 8-12 miles of walking/running; chest lifting; abs
day 2: 8-12 miles of walking/running; biceps, triceps, back lifting
day 3: 8-12 miles of walking/running; pilates leg workout; abs
day 4: 8-12 miles of walking/running; shoulders lifting
day 5: free day; my self-guilt usually results in me doing some cardio on the treadmill/elliptical
day 6: 8-12 miles of walking/running; bodyweight leg lifting; abs
day 7: 8-12 miles of walking/running
i separate my cardio work from my lifting by a few hours. i used to do lifting and cardio back-to-back at the gyms, but i like this schedule a lot better to give me a break. i also end up swimming quite a bit just about everyday.
i have recently tended to do high-reps with lower weights. last year, i would hammer curl 80-85 lbs. dumbbells for 8 reps each arm. now, im using 40 lbs. dumbbells and doing 18 reps. then, ill immediately do regular hanging arm curls with the dumbbells for a high number of reps. then, ill go right to cross-chest arm curls using the same dumbbells. if i do two complete sets of that routine, along with some back exercises, my arms are shot. it also gives me a better cardio workout than just doing 8 reps with heavy weights.
when lifting chest, i highly recommend doing push-ups immediately after each set. finish a lifting set of chest, then jump straight down to push-ups to do as many as you can do. do it to exhaustion. regardless if you can do 2 reps or 200 reps, do as many as you can right after each bench exercise. each time you do the push-ups, change your hand placement (regular, then wide, then lower towards your waist, then very close working more of your biceps).
when your muscles stop getting sore the next day after lifting or you are just bored with your routine, it is time to mix it up.
even in a caloric deficit, which you are wanting to cut weight, your strength is going to increase since you havent lifted in a while. dont worry about your strength not increasing since you are cutting calories. you will still increase your strength since you havent been lifting.
