Long, low intensity exercise casuses muscle LOSS??

I think this idea comes from the thought that if you have a big caloric deficit, you will lose body mass; if you aren't doing exercise that will stimulate the muscles like weightlifting, much of that loss will be muscle. So if you ONLY do low, low intensity exercise and you eat fewer calories than you burn, yes your muscles will shrink. Easily avoided if you continue to do some weight training and eat wisely (not a super low calorie crash diet where you try to lose many pounds per week).

But no, I have never seen any reputable source show that the low intensity exercise somehow causes your body to secrete some substance that eats up your muscle.

Anyone worrying about loss of lean muscle mass due to aerobic activity should read this:

https://physsportsmed.org/doi/10.3810/psm.2011.09.1933

Study population:

"Forty masters athletes (20 men and 20 women) were included in this study. Subjects were included if they were aged ≥ 40 years, trained for fitness and sports competitions ≥ 4 to 5 times per week, and did not have current sports-related injuries that limited their ability to compete in sports competitions. Many were age-group winners for their sport. The subjects were primarily composed of runners/track and field participants, bikers, and swimmers. "

Results:

"Per design, age was significantly different between groups. Although age groups did not differ in body weight, body mass index (BMI) tended to be higher in the group aged ≥ 70 years compared with the group aged 40 to 49 years. Those aged ≥ 70 years had a higher BF percentage and FM (Table 1). The LM was not significantly different across the age groups (P = 0.15) (Figure 2). Mid-thigh total muscle area was not different between age groups (P = 0.12). Quadriceps area was approximately 20% lower in the group aged ≥ 70 years compared with the groups aged 40 to 49 years and 50 to 59 years (P = 0.03). The SCAT and IMAT were not significantly different among groups (P = 0.41 and P = 0.31, respectively"

If you're consuming enough protein I wouldn't worry about it - it's broscience.

.... are you trying to say that the skinny-fat phenomena talked about on here thousands of times isn't real?

Skinny-fat is what people see when they have stripped out oll the excess bodyfat and have not done anything to maintain or increase muscle mass. The original poster does kayaking - I doubt very much that he will find a skinny-fat body under that excess fat.

It feels like there is a hysteria about lifting heavy at the moment like if we are not all pumping iron we will lose all our fat and find nothing but bones underneath!

There are LOADS of ways to maintain muscle mass without ever lifting a single bar or dumbbell. Your body is all the gymn you need and certainly your body in a kayak and working hard against water current.

Give me a river to swim in any day and you can keep your dumbbells. Each to their own.

As long as your diet is in check (not crash-dieting), have some protein after your workouts and some complex (slow) carbs before you workout, then you'll be fine.

There's a big obsession with "negative calories" with working out on an empty stomach to burn fat.. while that sounds awesome, it just doesn't work that way. Muscle is MUCH more nutritionally dense than fat, so as a result it's going to be cannibalized for energy before fat.

Also, putting "bro" before anything invalidates your post lol

... "bro-science", whatever the **** that's supposed to be.

Here you go.

1. Broscience
Broscience is the predominant brand of reasoning in bodybuilding circles where the anecdotal reports of jacked dudes are considered more credible than scientific research.

source:
http://www.urbandictionary.com/define.php?term=broscience

You validated the definition of "broscience" with your rejection of scientific studies.

... "bro-science", whatever the **** that's supposed to be.

Here you go.

1. Broscience
Broscience is the predominant brand of reasoning in bodybuilding circles where the anecdotal reports of jacked dudes are considered more credible than scientific research.

source:
http://www.urbandictionary.com/define.php?term=broscience

You validated the definition of "broscience" with your rejection of scientific studies.

thanks bigguy! i'll make sure to have my daughter refer to the urban dictionary (whatever the fk that is) when her next term paper is due. keep doing what you do. pencil neck lab techs doing 6 week experiments on starving college students that self report will always have all the correct answers. good job, bro!