Drew Eckhardt 

If you're going to ride intervals you want to do them when you're freshest following a rest day. I don't ride Sunday, so I do zone 5 intervals on Mondays. It takes two days with a recovery ride on Wednesday to recover from that, so my 1:00 - 1:30 zone 4 ride is on Thursday.

If you think you can't ride due to fatigue you need to go slower, perhaps embarrassingly slow with children on tricycles passing you.

Like most self-coached cyclists when I started trying to get fast my easy days weren't slow enough to allow recovery and build aerobic endurance, and I still occasionally fail to exercise enough restraint during my rest weeks.

You need to pedal faster to get your brain and muscles coordinated at higher speeds, although if you're riding intervals to get faster for weight loss or recreational purposes you want to ride 7-10 minutes as hard as you can sustain to maximize stress on the systems limiting your speed.

When doing that you need an easy week out of every 3-4 to allow adaptation to occur.

You don't need bigger muscles unless you're a track sprinter. 6-10 Calories a day per pound isn't a lot, especially compared to 500-1000 a day for 1-2 hours aerobic cycling at 150W.

At 200W (20 MPH for me and many other riders on "flat" ground) and 92 RPM you're looking at under 130 Newtons average and 184 peak which is 29 and 41 pounds of force respectively.

You have three energy systems. Muscle strength only limits the first.

1. Phosphagen powered by the creatine phosphate stored in your muscles. It's good for tens of seconds at best.

2. Glycolysis running off of glycogen in your liver and muscles. This is limited by how much oxygen you can get into your muscles and hydrogen ion/metabolite accumulation. Oxygen limits efforts of a few minutes (VO2max), and waste products longer efforts (lactate threshold/VT2). With enough fitness you could theoretically sustain a lactate threshold effort for 60 minutes although it won't be pleasant. "How I ache -- I can hardly move," Eddy Merckx told reporters after breaking the hour record. "It was the longest hour of my career ... It was terrible."

3. Your aerobic system powered mostly by fat. That lets other cyclists fly by at 20 MPH and maintain the pace for a hundred miles or more.

You want to improve the second and third.

You improve 2 most with 7-10 minute intervals.

3 gets better with riding lots of miles slower than a conversational pace (Friel heart rate zone 2, with the power zone varying based on how good your aerobic fitness is). Trying harder is counter-productive because it switches to your lactate system but doesn't stress it enough to cause improvements so you stay slow.

DarthMonkey

Drew has some good points and I understand where he is coming from, but I do disagree especially for someone just starting out. However weight loss and getting healthy isn't an exact science (more of an art form with some scientific principles) and there are multiple ways to get there. I suggest you read peoples opinions here, but do your own research.

You will probably see most fitness and medical experts recommend a combination of strength and cardio when trying to get fit. Higher resistance at slower pedal speed is as close to strength training as you will get on a bike. You mentioned you were on a fixed speed, so I would try one ride where you go for speed intervals on relatively flat stretches, and one where you route yourself through appropriate sized hills for some resistance intervals.

drew mentions zones. If you want to use these, good starting points are:
The Five Heart Rate Zones and Using Them in Your Workouts
Understanding Heart Rates & Cardio Training Zones

I would not attempt anything in zone 5 unless you have talked to your doctor.

Good luck

Francis73

If snacking is an issue you may want to look at the types of snacks vs not snacking, I tend to eat a banana or have a Greek yogurt for a snack now instead of the garbage I used to eat.

Francis73

With that being said though you still have to be mindful of how much you are eating or how many snacks you have.

DarthMonkey

Does the snacking revolve around down time activities like TV, computer, etc?

Consider these tips:

1) stay hydrated. mild dehydration can be mistaken for hunger. Keep an eye on your urine darkness to know if you are drinking enough. What The Color of Your Urine Says About You (Infographic) | Health Essentials from Cleveland Clinic
2) along the lines of #1 drink a big glass of water (make it an additional glass, so you drink your normal amount with your meal) before meals and before you decide to have a snack.
3) eat snacks slowly and stop to talk or do other things so you brain gets a chance to get the I'm full signal
4) Fiber and slow release proteins help you feel sated for longer
5) make sure you are engaged in whatever activity you are doing. Boredom can cause false hunger, for example just watching TV to have something on or something to do, but not being all that interested.
6) try to fix your sleep issues because that can mess with hunger signals and fat storage because the body is in a semi-stressed state
7) going online or watching TV before bed was giving me issues getting to sleep so now I stop watching tv and switch to my laptop about a hour before I want to go to bed. When I go on my laptop I read news or forums for 30 minutes to relax and get a little sleepy. I also use f.lux https://justgetflux.com/ to dim the blue light out of my laptop display in the evening so it doesn't keep me up like the TV used to.
8) I used to have a psychological\Pavlovian connection between evening TV and snacking. It took willpower and coming up with other things to do to keep my mind (and hands) occupied during that time over a period of a few weeks to break to connection. Now I only snack when I am actually hungry, and sometimes not even then unless I have macros\calories to "pay" for it.

Scott, YOU CAN DO THIS!

It was only about 4 months ago when I was where you are now (few weeks in an trying to figure out the best way forward). I used every resource I could get. Internet resources in general, these forums, picking the brains of family and friends with knowledge and experience (My wife and I are lucky to know personal trainers, doctors, successful weight losers and biking enthusiasts who all helped us sort though what we researched ourselves. I also recommend talking to your doctor) In the pursuit of more resources I joined a weight loss challenge at the gym to take advantage of what they offered (nutrition classes, body fat checks, changing weekly workouts, etc.) and to mix in some strength training. I have a long way to go, but I have greatly increased my biking endurance, speed, and hill climbing, added muscle and lost almost 30 pounds, which combined to drop my body fat percentage by about 9%.

Willbird

I have found living on a high carb diet coupled with high intensity riding causes a nearly overpowering urge to eat things not in my food plans for the day. My first 300 days or so of cut I was on second shift, and was going to eat my biggest meal of the day after my morning ride. I'm not sure if that helped, but it was easier then. It could just be more difficult as I have come closer to my goal weight too maybe. But a lower carb intake coupled with bumping zone 2 riding to 90% has almost totally banished that desire to "eat everything". If it is extremely windy it bumps me from zone 2 into higher zones, but enjoying the tailwind back home I keep my HR lower.

Jarrett2

OP, forget all that has been said. It's too much for someone just starting out.

Just start using MyFitnessPal.

Enter all the info they ask, then follow its direction.

Run Strava or MapMyRide on your phone when you ride. Take the post ride info and plug it into MyFitnessPal for exercise numbers.

Do that for a while. Watch the magic happen.

Willbird

I think information is a good thing. Yes just logging and not worrying about carb/fat/protein will work GREAT for 80% of the way for most folks. But then what do you do when you stall ? 999 of 1000 people revert to old well established habits and gain it all back plus some. BE the 1/1000 :-).

ShortLegCyclist

Veggies like broccoli, cauliflower, baby carrots and red peppers are a godsend when it comes to both snacking and avoiding snacking, because they are bulky and give you a sated feeling PLUS they are extremely low calorie.

You can add a little yogurt dip when starting out, but I tell you as I lost weight and got more and more active, my cravings and tastes changed... I stopped craving potato chips and started craving fresh veggies, strangest transformation ever for this former chicken wing addict... haven't had a wing in 18 months and the very thought of fried chicken makes me slightly nauseous now, instead I crave roasted cauliflower with Sriracha sauce now.

Veggies really, really help with giving you that sated, full feeling and I try to load up during lunch every day.

Willbird

My newest discovery is celery and gaucomole :-), yum :-). Fits in nice when you want to add some fat but not add carb or protein, 5/1/1 fat/protein/carb ratio :-)

indyfabz

Stopping will make it better. That is ultimately up to you alone as no one on this forum can keep you from snacking. At a minimum, don't keep crappy snack food in the house. Think apples, not Doritos.

Clyde1820

The thing that helped me most with in-between meal snacks has been: ensuring a reasonable combination of fat/protein/carb is in the thing; and, portion control.

Amazing, how far a 100-150cal serving can go, such as a few tablespoons of a great-quality yogurt (cultured whole milk only, not all the crummy additives), a few almonds, some chia seeds, perhaps half a banana. Fairly long-lasting basic energy, and not a bad replenishment following a workout, either, so long as electrolytes are consumed as well. Can dunk a carrot or banana or celery in a good peanut or almond butter (just the crushed nuts), for a boost in protein and fats. Can create a very simple blend with a half cup of fruit, some spinach leaves, a tablespoon of peanut butter and a couple tablespoons of yogurt.

That combination has worked wonders for nipping the edge off hunger, and for replacing all the essentially "bad" snack alternatives.

Four smaller meals, three snacks in between, all with a combination of fat/prot/carb, with as little sugar as possible, relatively lower carbs as compared to before, lower-glycemic where it can be done.

Jarrett2

THEN come back and ask for long, lengthy posts

Willbird

Everybody is different Jarrett2, some folks absorb information, it is something to think about while they are out riding EVERY DAY like they should, and I should, so with that I am gonna dress and get on my Bike :-).

Jarrett2

Fair enough. I'm going to mix it up today and do a little kayaking: